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17 páginas.- 7 figuras.- 2 tablas.- 53 referencias.- Supplementary Materials: The following are available online (at https://www.mdpi.com/article/10.3390/antiox10121888/s1), Epoxide metabolites from n-3 and n-6 polyunsaturated fatty acids arouse interest thanks to their physiological and pharmacological activities. Their chemical synthesis has significant drawbacks, and enzymes emerge as an alternative with potentially higher selectivity and greener nature. Conversion of eleven eicosanoid, docosanoid, and other n-3/n-6 fatty acids into mono-epoxides by fungal unspecific peroxygenases (UPOs) is investigated, with emphasis on the Agrocybe aegerita (AaeUPO) and Collariella virescens (rCviUPO) enzymes. GC-MS revealed the strict regioselectivity of the n-3 and n-6 reactions with AaeUPO and rCviUPO, respectively, yielding 91%-quantitative conversion into mono-epoxides at the last double bond. Then, six of these mono-epoxides were obtained at mg-scale, purified and further structurally characterized by 1H, 13C and HMBC NMR. Moreover, chiral HPLC showed that the n-3 epoxides were also formed (by AaeUPO) with total S/R enantioselectivity (ee > 99%) while the n-6 epoxides (from rCviUPO reactions) were formed in nearly racemic mixtures. The high regio- and enantioselectivity of several of these reactions unveils the synthetic utility of fungal peroxygenases in fatty acid epoxidation., Funding: This research was funded by BioBased Industries Joint Undertaking under the European Union’s Horizon 2020 Research and Innovation Programme, grant number 792063 (SusBind project; https://susbind.eu, accessed on 19 October 2021; to A.G., A.T.M. and M.H.), the BIO2017-86559-R and PID2020-118968RB-100 projects of the Spanish Ministry of Science & Innovation (co-financed by FEDER funds) to A.T.M. and A.G., respectively; the CSIC projects PIE-202040E185 (to A.G.) and PIE-202120E019 (to A.T.M.); and the CSIC SusPlast platform (to A.T.M.).

The spinel Li4Ti5O12 (LTO) is a promising lithium ion battery anode material with the potential to supplement graphite as an industry standard, but its low electrical conductivity and Li–ion diffusivity need to be overcome. Here, mesoporous LTO microspheres with carbon-coatings were formed by phase separation of a homopolymer from microphase-separated block copolymers of varying molar masses containing sol–gel precursors. Upon heating the composite underwent a sol–gel condensation reaction followed by the eventual pyrolysis of the polymer templates. The optimised mesoporous LTO microspheres demonstrated an excellent electrochemical performance with an excellent specific discharge capacity of 164 mA h g−1, 95% of which was retained after 1000 cycles at a C-rate of 10., The combination of block copolymer self-assembly and polymer phase separation with sol–gel chemistry enables the optimisation of Li4Ti5O12 (LTO) microspheres with size-tuneable carbon-coated mesopores, resulting in excellent electrochemical performance.

A bifunctional glycoside hydrolase GH78 from the ascomycete Xylaria polymorpha (XpoGH78) possesses catalytic versatility towards both glycosides and esters, which may be advantageous for the efficient degradation of the plant cell-wall complex that contains both diverse sugar residues and esterified structures. The contribution of XpoGH78 to the conversion of lignocellulosic materials without any chemical pretreatment to release the water-soluble aromatic fragments, carbohydrates, and methanol was studied. The disintegrating effect of enzymatic lignocellulose treatment can be significantly improved by using different kinds of hydrolases and phenoloxidases. The considerable changes in low (3 kDa), medium (30 kDa), and high (> 200 kDa) aromatic fragments were observed after the treatment with XpoGH78 alone or with this potent cocktail. Synergistic conversion of rape straw also resulted in a release of 17.3 mg of total carbohydrates (e.g., arabinose, galactose, glucose, mannose, xylose) per gram of substrate after incubating for 72 h. Moreover, the treatment of rape straw with XpoGH78 led to a marginal methanol release of approximately 17 μg/g and improved to 270 μg/g by cooperation with the above accessory enzymes. In the case of beech wood conversion, the combined catalysis by XpoGH78 and laccase caused an effect comparable with that of fungal strain X. polymorpha in woody cultures concerning the liberation of aromatic lignocellulose fragments.

Multiplications, mutations and dysregulation of the alpha synuclein gene (SNCA) are associated with the demise of dopaminergic neurons and are considered to play important roles in the pathogenesis of familial and sporadic forms of Parkinson’s disease. Regulation of SNCA expression might thus be an appropriate target for treatment. We aimed to identify specific modulators of SNCA transcription, generated CRISPR/Cas9 modified SNCA-GFP-luciferase (LUC) genomic fusion- and control cell lines and screened a library of 1649 bioactive compounds, including the FDA approved drugs. We found no inhibitors but three selective activators which increased SNCA mRNA and protein levels.

The Baeyer-Villiger or Beckmann rearrangements are established methods for the cleavage of ketone derivatives under acidic conditions, proceeding for unsymmetrical precursors selectively at the more substituted site. However, the fragmentation regioselectivity cannot be switched and fragmentation at the less-substituted terminus is so far not possible. We report here that the reaction of ketone enolates with commercial alkyl nitrites provides a direct and regioselective way of fragmenting ketones into esters and oximes or ω-hydroxyimino esters, respectively. A comprehensive study of the scope of this reaction with respect to ketone classes and alkyl nitrites is presented. Control over the site of cleavage is gained through regioselective enolate formation by various bases. Oxidation of kinetic enolates of unsymmetrical ketones leads to the otherwise unavailable "anti-Beckmann" cleavage at the less-substituted side chain, while cleavage of thermodynamic enolates of the same ketones represents an alternative to the Baeyer-Villiger oxidation or the Beckmann rearrangement under basic conditions. The method is suited for the transformation of natural products and enables access to orthogonally reactive dicarbonyl compounds.

El empleo de oxihidrógeno (HHO) en los motores de combustión interna de gran potencia, mejora su desempeño, en comparación con combustibles fósiles. El propósito de este trabajo es mostrar el potencial de producción electroquímica de HHO, así como el deterioro de sus electrodos. El proceso incluye el uso de reactores electroquímicos de celdas húmedas y secas, alimentadas con corriente continua. En este trabajo dichas celdas emplean soluciones acuosas 0.3 M y 1 M de hidróxido de sodio (NaOH) las cuales favorecen las reacciones de óxido reducción en los electrodos. El gas generado se recolecta, su composición es determinada por un equipo detector de gases portátil y se prueba su poder de combustión. El deterioro de las celdas se analiza identificando las variaciones físicas de los electrodos por inspección visual. Se comprueba la producción de HHO con un promedio de 1240 mililitros por minuto, con una relación 2:1 (H/O2). The use of oxyhydrogen (HHO) in high power internal combustion engines improves their performance compared to fossil fuels. The goal of this work is to show the potential of electrochemical production of HHO as well as the deterioration of its electrodes. The process involves the use of electrochemical reactors with wet and dry cells design, fed with direct current. In this work these cells used 0.3 M and 1 M aqueous solutions of sodium hydroxide (NaOH) which help redox reactions at the electrodes. The gas generated is collected, its composition is determined by a portable gas detector equipment and its combustion power is tested. The deterioration of the cells is analyzed, identifying the physical variations of the electrodes by visual inspection. HHO production is verified with an average of 1240 milliliters per minute, at a 2:1 ratio (H2/O).

We show the synthesis of an in vivo stable mercury compound with functionality suitable for radiopharmaceuticals. The designed cyclic bisarylmercury was based on the water tolerance of organomercurials, higher bond dissociation energy of Hg−Ph to Hg−S, and the experimental evidence that acyclic structures suffer significant cleavage of one of the Hg−R bonds. The bispidine motif was chosen for its in vivo stability, chemical accessibility, and functionalization properties. Radionuclide production results in 197(m)HgCl2(aq), so the desired mercury compound was formed via a water‐tolerant organotin transmetallation. The Hg‐bispidine compound showed high chemical stability in tests with an excess of sulfur‐containing competitors and high in vivo stability, without any observable protein interaction by human serum assay, and good organ clearance demonstrated by biodistribution and SPECT studies in rats. In particular, no retention in the kidneys was observed, typical of unstable mercury compounds. The natHg analogue allowed full characterization by NMR and HRMS., Stable and versatile: The cyclic bisarylmercury bispidine structure shows exceptional stability against sulfur compounds known to usually react very easily with mercury. Aside from its novelty in mercury chemistry, the in vivo stability paired with the functionalizability of this motif is an important step forward in the development of useful radiomercury pharmaceuticals.

Phytoprostanes (PhytoP) are natural products, which form in plants under oxidative stress conditions from α-linolenic acid. However, their epimers with relative prostaglandin configuration termed phytoglandins (PhytoG) have never been detected in Nature, likely because of the lack of synthetic reference material. Here, the first asymmetric total synthesis of such compounds, namely of PhytoGF1α (9-epi-16-F1t -PhytoP) and its diastereomer ent-16-epi-PhytoGF1α (ent-9,16-diepi-16-F1t -PhytoP), has been accomplished. The synthetic strategy is based on radical anion oxidative cyclization, copper(I)-mediated alkyl-alkyl coupling and enantioselective reduction reactions. A UHPLC-MS/MS study using the synthesized compounds as standards indicates PhytoG formation at significant levels during autoxidation of α-linolenic acid in edible vegetable oils. Initial testing of synthetic PhytoGs together with F1 -PhytoP and 15-F2t -IsoP derivatives for potential interactions with the PGF2α (FP) receptor did not reveal significant activity. The notion that PUFA-derived oxidatively formed cyclic metabolites with prostaglandin configuration do not form to a significant extent in biological or food matrices has to be corrected. Strong evidence is provided that oxidatively formed PhytoG metabolites may be ingested with plant-derived food, which necessitates further investigation of their biological profile.

Enhancement of the luminescence efficiency of two new diazapentacenium salts (D1 and D2) of more than 55 for D1 and 22 times for D2) in poor solvents, acetonitrile and/or dichloromethane, was observed and rationalized as formation of emissive J‐aggregates. Both compounds displaying 4‐n‐decylphenyl substituents at the 7,14‐carbons and phenyl (D1) or 2,6‐difluorophenyl (D2) substituents at the quaternary nitrogen atoms in 5,12‐positions have been synthetized in a two‐step procedure involving a two‐fold Buchwald‐Hartwig‐type CN cross‐coupling and an electrophilic Friedel‐Crafts‐type cyclization. The optical properties of the dicationic diazapentacenium salts in various solvents and in thin films have been investigated by steady‐state and time‐resolved absorption and photoluminescence spectroscopies. In thin films and in good solvents, isolated molecules coexist with aggregates. Nonetheless, D1 is seven times more emissive than D2, reflecting a higher J‐aggregate contribution in the former., Two new diazapentacenium salts have been obtained from a new synthetic methodology and shown to display a drastic increase of fluorescence quantum yields induced by aggregation (AIE phenomena) in poor solvents and associated to a particular type of aggregates organization: J‐aggregates. A simple structural modification (4 H in D1 vs 4 F in D2) changes the contribution of J‐aggregates which is quantitatively followed by time resolved fluorescence.

Diblock copolymer electrolytes based on a π-conjugated polyfluorene (PF) backbone were synthesized comprising nanodomains of a polymerized ionic liquid (PIL) and of a solid polymer electrolyte (SPE...

A fully soluble poly(9,10-anthrylene ethynylene), poly[2,6-(2-octyldecyl)-9,10-anthrylene ethynylene] PAAE, with moderate degrees of polymerization Pn of ca. 10 is generated in a reductive, dehalogenative homocoupling scheme, starting from a 2,6-dialkylated 9,10-bis(dibromomethylene)-9,10-dihydroanthracene monomer and n-BuLi/CuCN as the reducing agent. PAAE shows surprisingly broad and unstructured absorption and photoluminescence emission bands with peaks at 506 nm and 611 nm, respectively, both in chloroform solution. The long absorption tail ranging into the 600–700 nm region and the large Stokes shift points to a high degree of geometrical disorder in the arrangement of the 9,10-anthrylene chromophores along the distorted polymer backbone. This disorder is borne out in the unusually strong wavelength dependence of fluorescence depolarisation, both with regards to the excitation and the emission wavelengths. Picosecond fluorescence depolarisation spectroscopy provides clear evidence for the presence of orthogonal transition dipole moments, presumably arising from the off-axis transition of the anthracene unit and the on-axis transition of the polymer backbone. Intramolecular energy relaxation then gives rise to the observed fluorescence depolarization dynamics.

We report on the convenient synthesis of a CNC pincer ligand composed of carbazole and two mesoionic carbenes, as well as the corresponding lithium- and magnesium complexes. Mono-deprotonation affords a rare “naked” amide anion. In contrast to the proligand and its mono-deprotonated form, tri-deprotonated s-block complexes show bright luminescence, and their photophysical properties were therefore investigated by absorption- and luminescence spectroscopy. They reveal a quantum yield of 16% in solution at ambient temperature. Detailed quantum-chemical calculations assist in rationalizing the emissive properties based on an Intra-Ligand-Charge-Transfer (ILCT) between the carbazolido- and mesoionic carbene ligands. (Earth-)alkali metals prevent the distortion of the ligand following excitation and, thus, by avoiding non-radiative deactivation support bright luminescence., Lithium- and magnesium complexes of a CNC pincer ligand composed of carbazole and two mesoionic carbenes are bright luminescent, because the metals prevent molecular distortions upon excitation.

A range of plants developed leaves, the surfaces of which prevent or diminish insect adhesion due to their microscopic topography. Well known examples include the leaves of the lychee tree (Litchi chinensis). Here, we report a method to coat substrates with ethyl cellulose microparticles that exhibit wrinkled surfaces, resulting in surface morphologies that closely resemble those of insect repelling plants, i.e., Litchi chinensis. The microparticles were prepared by electrospraying, a method that allowed tuning of the particle size and surface morphology. By measuring the traction forces of Colorado potato beetles walking on these surfaces, the wrinkly microsphere parameters were optimized, resulting in biomimetic surfaces that surpass the antiadhesive properties of the biological role model. This study may pave the way to sustainable, nontoxic insecticide replacements.

Three new copolymers based on bay-annulated indigo (BAI) building blocks were synthesized through Stille-type cross-coupling reactions, alternating the electron-deficient BAI units with thiophene-based donor moieties. These polymers showed absorption and fluorescence emission in the NIR region. Their spatial structures were found to prevent aggregation-caused quenching (ACQ) in the solid state. Photoluminescence at 77 K is found ca. four times more intense than at 293 K. Based on time-resolved photoluminescence experiments, the excited-state energy transfer hopping deactivation in the copolymers is discussed in terms of a Förster-type mechanism, with time constants ranging from 1010 to 1011 s-1.

Gent, Gent, Belgium3Groningen Institute of Archaeology, University of Groningen, Groningen, The Netherlands4Eastern Atlas GmbH & CO. KG, Berlin, GermanyCorrespondenceJan Sevink, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, The Netherlands.Email: j.sevink@uva.nlScientific editing by Kevin Walsh1 | INTRODUCTIONSalt has long been an important commodity and it is therefore notsurprising that numerous archaeological studies have been devotedto its production (see e.g., Harding, 2013; Hocquet & Sarrazin, 2006;Nikolov & Bacvarov, 2012; Weller, 2002). Production techniqueshave ranged from mining (rock salt) and burning material containingsalts (plants and peat), to evaporation of saline waters to produce abrine from which salt is precipitated. Brines can be obtained in manyways, from collecting saline spring and seepage waters, or salt lakewater (e.g., sebkhas), to evaporation of seawater and leaching salineevaporation of sea water is by far the dominant raw material for salt production in the drier and warmer coastal areas of the world.Early salt production techniques based on evaporation of brines have been extensively studied, in many cases supported by ethno- graphic studies of such salt production in nonindustrial societies (see e.g., Cassen & Weller, 2013; Flad et al., 2005; Graham et al., 2015; Parsons, 2001; Weller, 2015; Williams, 2002). Two broad categories are distinguished: salt production using solar energy to evaporate a brine, and production based on boiling brine held in some sort of container (Weller, 2015). The first technique prevailed in Medi- terranean and warmer (semi‐)tropical climates favouring rapid eva- poration and was often based on evaporation from brines in salt pansAbstractA protohistoric (c.10th–5th c. BC) briquetage site at Puntone (Tuscany, Italy) was studied to unravel the salt production processes and materials involved. Geophysical surveys were used to identify kilns, pits, and dumps. One of these pits and a dump were excavated, followed by detailed chemical and physical analyses of the materials encountered. The pit had been used for holding brine, obtained by leaching of la- goonal sediment over a sieve, that afterwards was discarded to form large dumps. Phases distinguished indicate that the pit filled with fine sediment and was regularly “cleaned.” The presence of ferroan‐magnesian calcite in the pit fill testifies to the prolonged presence of anoxic brine. The production processes could be reconstructed in detail by confronting the analytical results with known changes in composition of a brine upon evaporation. These pertain in particular to the accumulation of “bitterns” and increased B (boron) concentrations in a residual brine. Both could be traced in the materials studied, and were found to be far more indicative than the ubiquitously studied concentrations of Cl and Na.

9 páginas.- 6 figuras.- 5 tablas.- 37 referencias.- The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.jafc.0c01019, Apocarotenoids are among the most highly valued fragrance constituents, being also appreciated as synthetic building blocks. This work shows the ability of unspecific peroxygenases (UPOs, EC1.11.2.1) from several fungi, some of them being described recently, to catalyze the oxyfunctionalization of α- and β-ionones and α- and β-damascones. Enzymatic reactions yielded oxygenated products such as hydroxy, oxo, carboxy, and epoxy derivatives that are interesting compounds for the flavor and fragrance and pharmaceutical industries. Although variable regioselectivity was observed depending on the substrate and enzyme, oxygenation was preferentially produced at the allylic position in the ring, being especially evident in the reaction with α-ionone, forming 3-hydroxy-α-ionone and/or 3-oxo-α-ionone. Noteworthy were the reactions with damascones, in the course of which some UPOs oxygenated the terminal position of the side chain, forming oxygenated derivatives (i.e., the corresponding alcohol, aldehyde, and carboxylic acid) at C-10, which were predominant in the Agrocybe aegerita UPO reactions, and first reported here., This work was supported by the EnzOx2 (H2020-BBI-PPP-2015-2-1-720297) EU-project and the CSIC (201740E071) project.

The self-assembly of a single layer of organic molecules on a substrate is a powerful strategy to modify surfaces and interfacial properties. Thiolates, silanes, phosphonates and carboxylates are widely used head-groups to link organic molecules to specific surfaces. In this study we show that self-assembly of perfluorododecyl iodide (I-PFC12) on a silicon nitride substrate leads to stable and highly compact monolayers of reproducible thickness (2.6 nm). Remarkably, the monolayers have the lowest ever reported surface energy of 2.6 mJ m(-2). The most likely mechanism leading to the formation of the monolayers is halogen bonding between the iodine in I-PFC12 and the nitrogen and oxygen atoms on the nitride. As a convenient, flexible and simple method, the self-assembly of halogen-bond driven perfluorocarbon monolayers is compatible with several applications, ranging from biosensing to electronics and microfluidics. Compared to other methods used to functionalise surfaces and interfaces, our procedure offers the unique advantage to work with extremely inert perfluorinated solvents. We demonstrate that surfaces commonly unstable in contact with many common organic solvents, such as organic-inorganic perovskites, can be functionalized via halogen bonding.

The DNA-linked inhibitor antibody assay (DIANA) has been recently validated for ultrasensitive enzyme detection and for quantitative evaluation of enzyme inhibitor potency. Here we present its adaptation for high-throughput screening of human carbonic anhydrase IX (CAIX), a promising drug and diagnostic target. We tested DIANA's performance by screening a unique compound collection of 2816 compounds consisting of lead-like small molecules synthesized at the Institute of Organic Chemistry and Biochemistry (IOCB) Prague ("IOCB library"). Additionally, to test the robustness of the assay and its potential for upscaling, we screened a pooled version of the IOCB library. The results from the pooled screening were in agreement with the initial nonpooled screen with no lost hits and no false positives, which shows DIANA's potential to screen more than 100,000 compounds per day.All DIANA screens showed a high signal-to-noise ratio with a Z' factor of0.89. The DIANA screen identified 13 compounds with

The effects of supplementation of standard media with metabolic intermediates (2 g/L butyric acid, 2 g/L butyric acid + 1.5 g/L acetic acid) on butanol and hydrogen production/yield were evaluated....

COMT- und MAO-B-Hemmer gehören neben den Dopamin-Agonisten und Levodopa zu den etablierten Pharmaka zur Behandlung des idiopathischen Parkinson-Syndroms (IPS). Die MAO-B-Hemmer Selegilin und Rasagilin entfalten auch in der Monotherapie einen symptomatischen Therapieeffekt, während Safinamid und COMT-Hemmer nur zur Kombinationstherapie mit Levodopa zugelassen sind. Beide Substanzklassen verlängern die Wirkdauer von Levodopa und optimieren die Wirkung der Therapie. Klinisch messbar resultiert eine Verlängerung der ON-Zeit. Der Einsatz von MAO-B-Inhibitoren erfolgte in der Vergangenheit auch unter der Vorstellung einer neuroprotektiven Wirkung. Trotz der aufgrund experimenteller Daten postulierten Wirkung ließ sich dieser Effekt in klinischen Studien bislang nicht zweifelsfrei belegen.

Background Participation in an assessment may change health behavior. This “mere-measurement effect” may be used for prevention purposes. However, little is known about whether individuals’ characteristics moderate the effect. The objective was to explore whether changes of physical activity (PA) and sedentary time (ST) after a cardiovascular assessment depend on sociodemographic variables and cardiometabolic risk factors. Methods A sample of n = 175 adults aged 40 to 65 received baseline assessment including self-administered PA and ST questionnaires and standardized measurement of blood pressure, waist circumference, and blood parameters. After 5 weeks, participants again reported PA and ST without any prior treatment or intervention. Linear regression models were used to analyze the dependence of five-week changes in PA and ST on baseline sociodemographic and cardiometabolic variables. Results Men increased transport-related PA more than women (b = 9.3 MET-hours/week, P = .031). Men with higher triglycerides increased transport-related PA less than men with lower triglycerides (b = − 5.6 MET-hours/week, P = .043). Men with higher systolic blood pressure reduced ST more than those with lower systolic blood pressure (b = − 35.7 min/week, P = .028). However, this linear association ceased to exist at a level of approximately 145 mmHg (b of squared association = 1.0, P = .080). A similar relationship was found for glycated hemoglobin and ST. Conclusions The findings suggest that sex and cardiometabolic risk factors moderate mere-measurement effects on PA and ST. Researchers and practitioners using mere measurement for prevention purposes may address PA and ST according to these individual characteristics. Trial registration ClinicalTrials.govNCT02990039. Registered 7 December 2016. Retrospectively registered.

We present a convenient three-step synthesis of amino substituted phosphazenyl phosphines of the general formula (R2N)3P=N–P(NR2)2 [NR2 = N(CH2)4, N(CH2)5, N(CH2)6]. These easily accessible mixed valent compounds display a surprisingly high proton affinity and basicity in the same range as the corresponding Schwesinger diphosphazene (Me2N)3P=N–P=NEt(NMe2)2 (Et-P2) and Verkade’s proazaphosphatrane superbases. Within the central [PIII–N=PV] scaffold, the phosphine PIII and not the phosphazene NIII atom is the center of highest proton affinity, basicity and donor strength. As P-bases, the title compounds display calculated proton affinities between 265.8 (NR2 = NMe2) and 274.7 kcal·mol–1 [NR2 = N(CH2)4] and pKBH+ values between 26.4 (NR2 = NMe2) and 31.5 [NR2 = N(CH2)4] on the acetonitrile scale. As P- nucleophiles, they are key intermediates in the synthesis of hyperbasic bis(diphosphazene) proton sponges, chiral bis(diphosphazene) proton pincers, bisphosphazides, and superbasic P2- bisylides. Their Staudinger reactions as nucleophile towards 1, 8-diazidonaphthalene leading to 1, 8-naphthalene-bisphosphazides is described in detail. The donor strength of the title compounds towards fragments [Se] and [Ni(CO)3] is in the same range as that of N-heterocyclic carbenes.

Two new polythiophenes functionalized with different degrees of tetraphenylethene, TPE, side groups (with TPE moieties at each thiophene unit, homoPT, and one in which only each second thiophene un...

This letter presents a 210–291-GHz $8\times $ multiplier chain in the 0.13- $\mu \text{m}$ SiGe Bipolar CMOS (BiCMOS) technology for the broadband generation of carrier signals, imaging, and spectroscopy. It consists of three cascaded Gilbert-cell doublers with compact input matching networks to generate quadrature collector currents in the switching quad for broadband flat conversion gain. The multiplier chain generates a saturated output power of −7.7 dBm at 244.5 GHz with a 3-dB bandwidth of 81 GHz. It consumes 0.24 W of dc power and occupies 0.86 mm 2 of chip area.

We report the results of a combined work based on density functional theory (DFT) calculations and experiments of the factors that influence the glass temperature, Tg, and the associated ion conduc...

In 1995 we extrapolated the so-called “effective conjugation length” in (para-phenylene) ladder polymers by relating the optical absorption energy to the reciprocal chain length of ladder-type oligo-(para-phenylene)s, but only based on three short-chain oligomers (a trimer, a pentamer, and a heptamer). The resulting value of 11–12 benzene rings was distinctly lower than the numbers reported for corresponding single-stranded, soluble poly(para-phenylene)s. Here, we report a series of elongated (para-phenylene)-type ladder oligomers that were isolated via repeated recycling size exclusion chromatography steps from an oligomer mixture. Now we are able to extrapolate the length of the “effectively conjugated segment” with much more precision to be 19 ± 2 benzene rings.

Introduction: Vitrectomy with peeling of epiretinal membrane (ERM) and internal limiting membrane offers the chance for improvement of metamorphopsia and visual acuity. Microscope integrated intraoperative optical coherence tomography (iOCT) enables real-time imaging of retinal alterations during peeling, such as intraoperative transient retinal thickening owing to tractional forces during peeling. The aim of our study was to measure the amounts of transient retinal thickening due to tractional forces during membrane peeling, as documented with iOCT, and to analyze possible effects on postoperative retinal function. Methods: This prospective, monocenter study included patients scheduled for pars plana vitrectomy with membrane peeling due to an idiopathic ERM. During peeling, an iOCT device (ReScan700, Carl Zeiss Meditec AG) with continuous OCT-assistance during the peeling procedure, and video documentation of the peeling procedure, was used for the assessment of intraoperative transient retinal thickening owing to tractional forces during peeling. Directly before and 3 months after surgery, macular-OCT scans and microperimetry were performed. Results: Twenty-five eyes of 25 patients were included in the study. Microperimetry could be performed in all patients, while iOCT documentation could be analyzed in 22 patients. Transient retinal thickening owing to tractional forces during peeling could be observed in 14 patients (64%), with a median thickening to 143% of the normal (preoperative) retinal thickness at that location (IQR 132–163). Six patients (24%) developed new deep microscotomata as seen in microperimetry 3 months after surgery, among them were 2 patients who also had transient retinal thickening during peeling. Conclusion: New deep microscotomata developed only in a minority of patients with transient retinal thickening owing to tractional forces during peeling.

Herein, we present a new class of singlet fission (SF) materials based on diradicaloids of carbene scaffolds, namely cyclic (alkyl)(amino)carbenes (CAACs). Our modular approach allows the tuning of two key SF criteria: the steric factor and the diradical character. In turn, we modified the energy landscapes of excited states in a systematic manner to accommodate the needs for SF. We report the first example of intermolecular SF in solution by dimer self‐assembly at cryogenic temperatures., Diradicaloids derived from cyclic carbenes are singlet‐fission molecules with exceptionally large diradicaloid character, which self‐assemble at cryogenic temperatures in solution.

Unspecific peroxygenases (UPOs) secreted by fungi represent an intriguing enzyme type that selectively transfers peroxide-borne oxygen with high efficiency to diverse substrates including unactivated hydrocarbons. They contain a cysteine-ligated heme and catalyze hydroxylation, epoxidation, dealkylation, deacylation as well as hetero atom, halide and one-electron oxidations. Substrate spectra of UPOs resemble both those of P450 monooxygenases and heme peroxidases.

In this Review, we showcase the fundamental processes of intermolecular and intramolecular singlet fission (SF). Furthermore we prioritize the information, which is relevant for the implementation of SF and SF-materials into solar energy conversion devices. We do this, firstly, by referring to the complexity of SF, and discussing key aspects of it; secondly, by mentioning the instrumental efforts, which assisted in unraveling SF in benchmark molecular building blocks such as tetracene, pentacene, and their corresponding dimers/oligomers; thirdly, by presenting a collection of SF-materials, as well as available photophysical and electrochemical data for energy conversion research. Among others, these include perylene-diimides (PDIs), diketopyrrolopyrroles (DPPs), carotenoids, conjugated polymers, and diradicaloids. This Review is rounded off by discussing pioneering contributions of SF in solar energy conversion schemes and highlighting recent developments in the field. Overall, a set of guidelines is given for new directions in SF, that is, the use of new tools to discover new SF-materials (i.e. spectroscopy, computation, machine-learning) and deposition processes (i.e. thin-films, DSSCs, OPVs) to couple SF-materials with the appropriate semiconductors.

Three new polymers containing tetraphenylethylene and diphenyl-dinaphthylethylene cores and their corresponding monomeric model compounds were synthesized and fully characterized aiming to investigate their photoluminescence efficiency, microporosity and Brunauer–Emmett–Teller-derived surface areas (SBET). Comprehensive photophysical characterization was undertaken in the solid state (powder and thin films), in tetrahydrofuran (THF) solution and in mixtures of “good” and “poor” solvent to induce aggregation (THF:water mixtures). Aggregation induced emission (AIE) was found for the tert-butyl-TPE monomer and polymer and diphenyl-dinaphthylethylene monomer with the increase of the water amount in THF:water mixtures and in the solid state. The tert-butyl substituted TPE derivatives display the highest fluorescence quantum yield (ϕF) values: 0.14 to 0.30 (in powder) and 0.46 to 0.64 in thin films. In contrast, with the diphenyl-dinaphthylethylene (meta and para-phenylene) polymers aggregation caused quenching (ACQ) occurs in THF:water mixtures (ϕF ≤ 0.011) and in the solid state (ϕF ≤ 0.012). The microporosity of the soluble conjugated polymers as potential conjugated polymers of intrinsic microporosity (cPIMs) was further investigated. The SBET of the polymers were related to their optical properties. The polymers show an attractive combination of high SBET surface area (417 m2 g−1) and the occurrence of distinct AIE effects for the tert-butyl-TPE polymer while the diphenyl-dinaphthylethylene polymers do not exhibit microporosity (SBET ≤ 17 m2 g−1) and show ACQ behavior.

Nanotechnology 33(1), 015601 (1-11) (2022). doi:10.1088/1361-6528/ac29d8, Misfit strain in core���shell nanowires can be elastically released by nanowire bending in case of asymmetric shell growth around the nanowire core. In this work, we investigate the bending of GaAs nanowires during the asymmetric overgrowth by an In$_x$Ga$_{1���x}$As shell caused by avoiding substrate rotation. We observe that the nanowire bending direction depends on the nature of the substrate's oxide layer, demonstrated by Si substrates covered by native and thermal oxide layers. Further, we follow the bending evolution by time-resolved in situ x-ray diffraction measurements during the deposition of the asymmetric shell. The XRD measurements give insight into the temporal development of the strain as well as the bending evolution in the core���shell nanowire., Published by IOP Publ., Bristol

Photo-oxa-dibenzocyclooctyne (Photo-ODIBO) undergoes photodecarbonylation under UV excitation to its bright S2 state, forming a highly reactive cyclooctyne, ODIBO. Following 321 nm excitation with sub-50 fs actinic pulses, the excited state evolution and cyclopropenone bond cleavage with CO release were characterized using femtosecond stimulated Raman spectroscopy and time-dependent density functional theory Raman calculations. Analysis of the photo-ODIBO S2 CO Raman band revealed multi-exponential intensity, peak splitting and frequency-shift dynamics. This suggests a stepwise cleavage of the two C–C bonds in the cyclopropenone structure that is completed within

Metal fluorides, promising lithium-ion battery cathode materials, have been classified as conversion materials due to the reconstructive phase transitions widely presumed to occur upon lithiation. We challenge this view by studying FeF3 using X-ray total scattering and electron diffraction techniques that measure structure over multiple length scales coupled with density functional theory calculations, and by revisiting prior experimental studies of FeF2 and CuF2. Metal fluoride lithiation is instead dominated by diffusion-controlled displacement mechanisms, and a clear topological relationship between the metal fluoride F− sublattices and that of LiF is established. Initial lithiation of FeF3 forms FeF2 on the particle’s surface, along with a cation-ordered and stacking-disordered phase, A-LixFeyF3, which is structurally related to α-/β-LiMn2+Fe3+F6 and which topotactically transforms to B- and then C-LixFeyF3, before forming LiF and Fe. Lithiation of FeF2 and CuF2 results in a buffer phase between FeF2/CuF2 and LiF. The resulting principles will aid future developments of a wider range of isomorphic metal fluorides. Metal-fluoride-based lithium-ion battery cathodes are typically classified as conversion materials because reconstructive phase transitions are presumed to occur upon lithiation. Metal fluoride lithiation is now shown to be dominated instead by diffusion-controlled displacement mechanisms.

Significance Vaccines profit from the addition of adjuvants to better and more specifically initiate, amplify, and shape immune responses. Although the number of adjuvant candidates has steadily increased, peaking in the current SARS-CoV-2 pandemic, little is known about their inherent mode of action. Using human blood immune cells, we established a multilayer method to systematically assess the adjuvants’ effects on innate and adaptive immune cells. By employing a multiplex analysis with cells from 30 different donors, we determined important patterns of adjuvant function. Moreover, we demonstrate correlates of an antiviral immune response using a Toll-like receptor 7/8 ligand adjuvant and single-stranded RNA. This knowledge about adjuvants’ distinct immune signatures supports the selection of safe and effective adjuvants for future vaccines., The COVID-19 pandemic highlights the importance of efficient and safe vaccine development. Vaccine adjuvants are essential to boost and tailor the immune response to the corresponding pathogen. To allow for an educated selection, we assessed the effect of different adjuvants on human monocyte-derived dendritic cells (DCs) and their ability to polarize innate and adaptive immune responses. In contrast to commonly used adjuvants, such as aluminum hydroxide, Toll-like receptor (TLR) agonists induced robust phenotypic and functional DC maturation. In a DC-lymphocyte coculture system, we investigated the ensuing immune reactions. While monophosphoryl lipid A synthetic, a TLR4 ligand, induced checkpoint inhibitors indicative for immune exhaustion, the TLR7/8 agonist Resiquimod (R848) induced prominent type-1 interferon and interleukin 6 responses and robust CTL, B-cell, and NK-cell proliferation, which is particularly suited for antiviral immune responses. The recently licensed COVID-19 vaccines, BNT162b and mRNA-1273, are both based on single-stranded RNA. Indeed, we could confirm that the cytokine profile induced by lipid-complexed RNA was almost identical to the pattern induced by R848. Although this awaits further investigation, our results suggest that their efficacy involves the highly efficient antiviral response pattern stimulated by the RNAs’ TLR7/8 activation.

Background To establish effective infection control protocols, understanding pathogen transmission pathways is essential. Non-infectious surrogate tracers may safely explore these pathways and challenge pre-existing assumptions. We used silica nanoparticles with encapsulated DNA (SPED) for the first time in a real-life hospital setting to investigate potential transmission routes of vancomycin-resistant enterococci in the context of a prolonged outbreak. Methods The two study experiments took place in the 900-bed University Hospital Zurich, Switzerland. A three-run 'Patient experiment' investigated pathogen transmission via toilet seats in a two-patient room with shared bathroom. First, various predetermined body and fomite sites in a two-bed patient room were probed at baseline. Then, after the first patient was contaminated with SPED at the subgluteal region, both patients sequentially performed a toilet routine. All sites were consequently swabbed again for SPED contamination. Eight hours later, further spread was tested at predefined sites in the patient room and throughout the ward. A two-run 'Mobile device experiment' explored the potential transmission by mobile phones and stethoscopes in a quasi-realistic setting. All SPED contamination statuses and levels were determined by real-time qPCR. Results Over all three runs, the 'Patient experiment' yielded SPED in 59 of 73 (80.8%) predefined body and environmental sites. Specifically, positivity rates were 100% on subgluteal skin, toilet seats, tap handles, and entertainment devices, the initially contaminated patients' hands; 83.3% on patient phones and bed controls; 80% on intravenous pumps; 75% on toilet flush plates and door handles, and 0% on the initially not contaminated patients' hands. SPED spread as far as doctor's keyboards (66.6%), staff mobile phones (33.3%) and nurses' keyboards (33.3%) after eight hours. The 'Mobile device experiment' resulted in 16 of 22 (72.7%) positive follow-up samples, and transmission to the second patient occurred in one of the two runs. Conclusions For the first time SPED were used to investigate potential transmission pathways in a real hospital setting. The results suggest that, in the absence of targeted cleaning, toilet seats and mobile devices may result in widespread transmission of pathogens departing from one contaminated patient skin region., Antimicrobial Resistance and Infection Control, 11 (1), ISSN:2047-2994

Background: Fungal DyP-type peroxidases have so far been described exclusively for basidiomycetes. Moreover, peroxidases from ascomycetes that oxidize Mn2+ ions are yet not known. Methods: We describe here the physicochemical, biocatalytic, and molecular characterization of a DyP-type peroxidase (DyP, EC 1.11.1.19) from an ascomycetous fungus. Results: The enzyme oxidizes classic peroxidase substrates such as 2,6-DMP but also veratryl alcohol and notably Mn2+ to Mn3+ ions, suggesting a physiological function of this DyP in lignin modification. The KM value (49 µM) indicates that Mn2+ ions bind with high affinity to the XgrDyP protein but their subsequent oxidation into reactive Mn3+ proceeds with moderate efficiency compared to MnPs and VPs. Mn2+ oxidation was most effective at an acidic pH (between 4.0 and 5.0) and a hypothetical surface exposed an Mn2+ binding site comprising three acidic amino acids (two aspartates and one glutamate) could be localized within the hypothetical XgrDyP structure. The oxidation of Mn2+ ions is seemingly supported by four aromatic amino acids that mediate an electron transfer from the surface to the heme center. Conclusions: Our findings shed new light on the possible involvement of DyP-type peroxidases in lignocellulose degradation, especially by fungi that lack prototypical ligninolytic class II peroxidases.

ConspectusOne of the constant challenges of synthetic chemistry is the molecular design and synthesis of nonionic, metal-free superbases as chemically stable neutral organic compounds of moderate molecular weight, intrinsically high thermodynamic basicity, adaptable kinetic basicity, and weak or tunable nucleophilicity at their nitrogen, phosphorus, or carbon basicity centers. Such superbases can catalyze numerous reactions, ranging from C-C bond formation to cycloadditions and polymerization, to name just a few. Additional benefits of organic superbases, as opposed to their inorganic counterparts, are their solubility in organic reaction media, mild reaction conditions, and higher selectivity. Approaching such superbasic compounds remains a continuous challenge. However, recent advances in synthetic methodology and theoretical understanding have resulted in new design principles and synthetic strategies toward superbases. Our computational contributions have demonstrated that the gas-phase basicity region of 350 kcal mol-1 and even beyond is easily reachable by organosuperbases. However, despite record-high basicities, the physical limitations of many of these compounds become quickly evident. The typically large molecular weight of these molecules and their sensitivity to ordinary reaction conditions prevent them from being practical, even though their preparation is often not too difficult. Thus, obviously structural limitations with respect to molecular weight and structural complexity must be imposed on the design of new synthetically useful organic superbases, but strategies for increasing their basicity remain important.The contemporary design of novel organic superbases is illustrated by phosphazenyl phosphanes displaying gas-phase basicities (GB) above 300 kcal mol-1 but having molecular weights well below 1000 g·mol-1. This approach is based on a reconsideration of phosphorus(III) compounds, which goes along with increasing their stability in solution. Another example is the preparation of carbodiphosphoranes incorporating pyrrolidine, tetramethylguanidine, or hexamethylphosphazene as a substituent. With gas-phase proton affinities of up to 300 kcal mol-1, they are among the top nonionic carbon bases on the basicity scale. Remarkably, the high basicity of these compounds is achieved at molecular weights of around 600 g·mol-1. Another approach to achieving high basicity through the cooperative effect of multiple intramolecular hydrogen bonding, which increases the stabilization of conjugate acids, has recently been confirmed.This Account focuses on our efforts to produce superbasic molecules that embody many desirable traits, but other groups' approaches will also be discussed. We reveal the crucial structural features of superbases and place them on known basicity scales. We discuss the emerging potential and current limits of their application and give a general outlook into the future.

The impact of water on odor-active compounds in fermented and dried cocoa beans as well as in chocolate either produced by a novel processing (NPC) or a traditional processing (TPC) technology from the same batch of cocoa beans was investigated in this study. Quantitation of selected key odorants revealed significantly higher concentrations of Strecker aldehydes such as 3-(methylsulfanyl)propanal (66-fold) and phenylacetaldehyde (50-fold) after water treatment of the cocoa beans. The comparison of the two chocolates showed that higher amounts of the Strecker aldehydes 2-methylbutanal, 3-methylbutanal, and phenylacetaldehyde are released with water in the NPC (24-fold to 39-fold), compared to the TPC (7.3-fold-11-fold). In addition to Strecker aldehydes, the concentrations of many further characteristic key odorants of cocoa and chocolate increased after water treatment. Based on the results, a more intense retronasal odor perception of the analyzed compounds is expected due to their release during consumption in contact with saliva.

This study provides an insight into possible recycling processes for autoclaved aerated concrete (AAC) at low temperatures (&lt, 1000 °C). Belite binders were synthesized from wastes of AAC by the addition of CaCO3 and adaption of the molar CaO/SiO2 (C/S ratio) in the range of 2 to 2.5. An in situ XRD study performed during heating up to 1000 °C and subsequent quenching to room temperature evidenced the formation of ternesite besides C2S in sulfate-containing systems. Several factors influencing the reaction kinetics and the evolution of the phase composition were investigated thoroughly. Increased sulfate content and dwelling time during heating increase the ternesite content and promote the formation of highly crystalline α’H-C2S. The C/S-ratio of the starting materials has to be adjusted to the sulfate content in order to prevent the formation of ternesite at the expense of C2S. Ternesite remains stable during quenching to room temperature or even increases in amount, except in cases of very low cooling rates or high residual quartz contents (C/S-ratio ≤ 2). Temperature and range of α’H-C2S to β-C2S phase transition on quenching strongly depend on the cooling rate. The onset temperature for β-C2S formation varies between 540 °C (slow quench) and 450 °C (fast quench). Thermal expansion coefficients of ternesite are calculated showing similarity with C2S. The incorporation of CaSO4 modules in the structure switches the direction of maximum compression.

Percutaneous coronary intervention is the most often used method for coronary revascularization. Stenting restores blood perfusion to ischemic areas, but it also causes mechanical disruption of the atheromatous plaque and the nearby endothelium, stimulating the activation of platelets. In a similar way, platelets are activated by thrombin exposure in the setting of plaque rupture. The interaction between platelets, oxidative stress and inflammation is an important factor determining the extent and severity of vascular dysfunction observed in these settings. Platelets activated by the vessel trauma release inflammatory and mitogenic mediators into the vascular microenvironment, activating leukocyte chemotaxis and switching the endothelial phenotypefrom a quiescent to an activate one. The increased bioavailability of reactive oxygen species from the vessel wall, from leukocytes and from platelets, and the subsequent decreased bioavailability of nitric oxide, further stimulates platelets, which are otherwise inhibited by this endothelial mediator. Thus, inflammation, oxidative stress and platelet activation cooperate in a feed-forward mechanism leading to vascular dysfunction and possibly compromising the effect of stenting. Inhibitors of platelet function have thus important ancillary effects beyond their antithrombotic ones, which will be discussed in the present short review.

The reaction of aryl- and amino(dihydro)boranes with dibora[2]ferrocenophane 1 leads to the formation 1,3-trans-dihydrotriboranes by formal hydrogenation and insertion of a borylene unit into the B=B bond. The aryltriborane derivatives undergo reversible photoisomerization to the cis-1,2-μ-H-3-hydrotriboranes, while hydride abstraction affords cationic triboranes, which represent the first doubly base-stabilized B3 H4+ analogues.

With the synthesis of N, N′, N″, N‴-tetrakis(3- (dimethylamino)propyl)triaminophosphazene (TDMPP, 1), we present the first phosphazene superbase with enhanced basicity through the effect of multiple intramolecular hydrogen bonding (IHB). Due to intramolecular solvation of four NH protons, the proton affinity is even higher than that of second-order phosphazene (dma)P2-tBu. X-ray structural proof, NMR titration experiments, and computational investigations provide a more detailed quantitative description of the IHB influence on the superbasicity of 1 in solid-state, solution, and the gas-phase.

Acta haematologica 143(3), 217-231 (2020). doi:10.1159/000501927, Published by Karger, Basel

During somatic hypermutation (SHM) of Ig genes in germinal center B cells, lesions introduced by activation-induced cytidine deaminase are processed by multiple error-prone repair pathways. Although error-free repair by homologous recombination (HR) is crucial to prevent excessive DNA strand breakage at activation-induced cytidine deaminase off-target genes, its role at the hypermutating Ig locus in the germinal center is unexplored. Using B cell–specific inactivation of the critical HR factor Brca2, we detected decreased proliferation, survival, and thereby class switching of ex vivo–activated B cells. Intriguingly, an HR defect allowed for a germinal center reaction and affinity maturation in vivo, albeit at reduced amounts. Analysis of SHM revealed that a certain fraction of DNA lesions at C:G bp was indeed repaired in an error-free manner via Brca2 instead of being processed by error-prone translesion polymerases. By applying a novel pseudo-time in silico analysis of mutational processes, we found that the activity of A:T mutagenesis during SHM increased during a germinal center reaction, but this was in part defective in Brca2-deficient mice. These mutation pattern changes in Brca2-deficient B cells were mostly specific for the Ig V region, suggesting a local or time-dependent need for recombination repair to survive high rates of SHM and especially A:T mutagenesis.

A mild, atom-economic, and metal-free α-C-H amination of ethers using relatively stable nonafluorobutanesulfonyl (nonaflyl, Nf) azide as the aminating reagent to give N-sulfonyl hemiaminals is reported. This enables unprecedented C(sp3 ) difunctionalization reactions, leading to diverse functionalized amino group containing compounds starting from simple ethers in one pot.

Controversy remains about how diet affects the vascular endothelial dysfunction associated with disordered insulin-glucose homeostasis. It is postulated that the type and level of certain macronutrients contribute to endothelial dysfunction in vascular diabetes complications. However, it is not well understood how specific macronutrients affect the molecular inflammatory response under conditions of hyperglycemia. Here, we examined retinal microvascular endothelial injury in streptozotocin (STZ)-diabetic rats fed a laboratory Western diet (WD). WD, characterized by its high content of saturated fat, cholesterol, and sugar, significantly increased retinal leukocyte accumulation and endothelial injury in the STZ-diabetic rats. Suppression of endothelial NF-κB signaling in the STZ model reduced the WD-induced increase in leukocyte accumulation. To isolate the effect of dietary fat, we generated high-fat diets with varying fatty acid balance and type. These diets contained moderate amounts of carbohydrates but no sugar. We found that neither high levels of saturated or unsaturated fats per se increased retinal leukocyte accumulation and endothelial injury in the STZ-diabetic rat model but that the combination of high levels of dietary cholesterol with specific saturated fatty acids that are abundant in WD exacerbated leukocyte accumulation and endothelial injury in the retinas of STZ-diabetic rats.—Barakat, A., Nakao, S., Zandi, S., Sun, D., Schmidt-Ullrich, R., Hayes, K. C., Hafezi-Moghadam, A. In contrast to Western diet, a plant-based, high-fat, low-sugar diet does not exacerbate retinal endothelial injury in streptozotocin-induced diabetes.