Crystalline Complex Research Articles

Provenance and U–Pb Ages of Detrital Zircons from the Sandstones of the Middle Devonian Asyvvozh Formation, Dzhezhimparma Highland, Southern Timan

Results of U–Pb dating of detrital zircon grains from diamond-bearing sandstones of the Middle Devonian Asyvvozh Formation in the Southern Timan are presented. It was established that the sandstones do not contain zircon grains younger than the Middle Riphean. The datings of 92 zircon grains fall in the interval of 1144 ± 36 to 3090 ± 19 Ma, and the difference between the depositional age of the Middle Devonian sandstones and the age of the youngest zircons is around 750 m.y. The main sources of terrigenous material during the deposition of the Asyvvozh sandstones were the crystalline complexes of the ancient basement of the East European Craton (the central regions of Volga–Uralia) and the complexes of accretionary orogens on the margins of Baltica. The presumably Cambrian kimberlites located within the Komi–Permyak and Sysola arches of the basement of the East European Craton could have been the sources of diamonds.

Chromium-rich vanadio-oxy-dravite from the Tzarevskoye uranium–vanadium deposit, Karelia, Russia: a second world-occurrence of Al–Cr–V–oxy-tourmaline

AbstractA green tourmaline sample from the Tzarevskoye uranium–vanadium deposit, close to the Srednyaya Padma deposit, Lake Onega, Karelia Republic, Russia, has been found to be the second world-occurrence of Cr-rich vanadio-oxy-dravite in addition to the Pereval marble quarry, Sludyanka crystalline complex, Lake Baikal, Russia, type-locality. From the crystal-structure refinement and chemical analysis, the following empirical formula is proposed: X(Na0.96K0.02□0.02)Σ1.00Y(V1.34Al0.68Mg0.93Cu2+0.02Zn0.01Ti0.01)Σ3.00Z(Al3.19Cr1.36V0.03Mg1.42)Σ6.00(TSi6O18)(BBO3)3V(OH)3W[O0.60(OH)0.23F0.17]Σ1.00. Together with the data from the literature, a compositional overview of Al–V–Cr–Fe3+-tourmalines is provided by using [6]Al–V–Cr–Fe3+ diagrams for tourmaline classification. These diagrams further simplify the tourmaline nomenclature as they merge the chemical information over the octahedrally-coordinated sites (Y and Z) by removing the issues of uncertainty associated with cation order–disorder across Y and Z. Results show the direct identification of tourmalines by using the chemical data alone.

Iron phosphomolybdate complexes in electrocatalytic reduction of aqueous disinfection byproducts

The crystalline iron phosphomolybdate-bipyridylpropane complex (FePM-BPP) synthesized by hydrothermal method in water possesses two [P4Mo6VO31]12− subunits bridged by one Fe center. We discovered that the FePM-BPP complex is an electrocatalyst active at close-to-neutral pH in aqueous electrolytes, catalyzing reduction of a variety of carcinogenic disinfection byproducts (DBPs) such as chloroform, N-nitrosodimethylamine (NDMA), and bromate. Deposition of FePM-BPP onto the surface of carbon electrodes led to accelerated chloroform electroreduction at near-neutral pH, at potentials in the −0.52 to −0.27 V vs standard hydrogen electrode (SHE) range, with surface-normalized rate constant of chloroform reduction at ca. 140 L m-2h−1, and over 40% of chloroform reduced at −0.27 V vs SHE after 1 h. The surface-normalized first-order rate constants of the NDMA and bromate electroreduction at − 0.77 V vs SHE and pH 5.5 or 6.4 were estimated to be 250 and 150 L m-2h−1, respectively. The simple synthetic route with low-cost, earth-abundant components, and versatility indicate that FePM-BPP can be considered for incorporation into DBP reduction processes as a heterogeneous catalyst.

Monazite geochronology in melt-percolated UHP meta-granitoids: An example from the Erzgebirge continental subduction wedge, Bohemian Massif

Coupled age and trace element mapping in monazite grains using the Laser-Ablation Split-Stream ICP-MS technique was carried out for a sequence of samples from (U)HP crustal section in the Eger Crystalline Complex interpreted as a Variscan continental subduction wedge. The sampled section comprises banded orthogneiss with monazite protolith ages of 486 ± 3[10] Ma. The orthogneiss was heterogeneously transformed to migmatite, HP felsic granofels and U(HP) fine-grained Ky-Kfs granulite during coupled deformation and percolation of silicate melts in a subduction channel. Age of the (U)HP metamorphism and related melt percolation in the granulite is dated by Th-rich and HREE-poor monazite cores at 353.6 ± 2.7[8] Ma, that are in equilibrium with HREE-rich garnets. Th-rich cores of monazites in the migmatite, granofels and granulite that lack the (U)HP signatures show younger ages of 347.8 ± 3.4[8] Ma, 345.8 ± 2.4[8] Ma and 339.3 ± 1.3[7] Ma, respectively. The monazite rims with lower Th and higher HREE contents than the monazite cores are likely a result of (re)crystallization in equilibrium with melt that partly dissolved the HREE-rich prograde garnet during decompression. This (re)crystallization is constrained by ages of 344.2 ± 1.6[8] Ma in (U)HP granulites and 338–340 ± [8] Ma in migmatites, granofelses and granulites without the (U)HP signature. The groups of ages from 353 Ma to 338 Ma, are significantly different when only their in-run uncertainties (7–10 Ma) are compared and indicate a 15 ± 3 Ma period of monazite (re)crystallization from burial/peak to exhumation.

Chromium Diamino-bis(phenolate) Complexes as Catalysts for the Ring-Opening Copolymerization of Cyclohexene Oxide and Carbon Dioxide.

Chromium diamino-bis(phenolate) complexes, CrXL [where L = 6,6'-((1,4-diazepane-1,4-diyl)bis(methylene))bis(2,4-dimethylphenolato) and X = Cl- (1), OH- (2), and N3- (3)], were prepared and characterized by MALDI-TOF MS and single-crystal X-ray diffraction. Complex 1 crystallized as two linkage isomers, specifically a green chloride-bridged dimer (1) and a pink asymmetrically bridged isomer exhibiting one chloride bridging atom and one bridging phenolate oxygen (1'). Adventitious moisture during sample handling causes the formation of hydroxide-containing complex 2. The reaction of 1 with PPNN3 (where PPN = bis(triphenylphosphine)iminium) permits the isolation of a crystalline chromium azide complex, 3, which was structurally authenticated. Complex 1 showed good activity toward the ring-opening copolymerization of cyclohexene oxide and carbon dioxide with an added chloride, azide, or 4-(dimethylamino)pyridine (DMAP) cocatalyst to give a completely alternating polycarbonate with a narrow molecular weight dispersity.

Synthesis of Glibenclamide-Oxalic Acid Cocrystal using ThermalSolvent-Free Method

Solubility is an important parameter affecting the bioavailability of drugs. The solubility of an active pharmaceutical ingredient (API) could be improved through the formation of cocrystal, which is a crystalline complex composed of two or more different molecules. Glibenclamide (GCM) is an API with poor solubility in water, which belongs to class II, characterized as highly permeable with low solubility. Therefore, this study aimed to synthesize and characterize the cocrystal of GCM-oxalic acid (OA) using the melting method. The interaction between GCM-OA complexes was predicted using the in silico method. Also, the cocrystal complexes were characterized by differential scanning calorimetry (DSC), infrared (IR) spectrophotometry, and powder X-ray diffraction (PXRD), as well as, through solubility and dissolution tests. The result showed that GCM and OA have the potential of forming cocrystal through the in silico method. Also, the cocrystal of GCM-OA with a molar ratio 1:2, significantly improved the solubility and dissolution profile of GCM. In addition, the spectrum IR of cocrystal exhibited a shifting peak at 1,700 cm-1 indicating the presence of intermolecular interaction between GCM and OA. Furthermore, the DSC and PXRD analyses showed a new single endothermic peak and new diffraction peak pattern, respectively, indicating the formation of a new crystalline component.

The late Miocene Öksüt high sulfidation epithermal Au-Cu deposit, Central Anatolia, Turkey: Geology, geochronology, and geochemistry

The Öksüt high sulfidation (HS) epithermal Au (-Cu) deposit (35.32 million tonnes of ore at 1.22 g/t Au) is located in the Central Anatolian Volcanic Province (CAVP) at the south-eastern segment of the Central Anatolian Crystalline Complex (CACC). The deposit is hosted by large hydrothermal breccia bodies and hornblende-rich basaltic andesite porphyry of the Develidag Volcanic Complex (DVC), which were pervasively altered to form silicification and argillic assemblages. The host rocks and mineralization are covered by post-mineral pyroxene-rich basaltic andesite of DVC. The volcanic rocks have a medium-K calc-alkaline affinity similar to regional volcanic rocks of the DVC. The gold and copper mineralization is mostly associated with quartz and primary sulfides hosted by silicification and argillic alteration particularly quartz-alunite cemented breccias and subsequently enriched by supergene oxidation processes causing destabilization of the primary sulfides.The LA-ICP-MS zircon U-Pb geochronology indicates a range of 206Pb/238U ages between 5.4 and 6.0 Ma with an average mean age of autocrystic grains of 5.73 ± 0.06 Ma for the host hornblende-rich basaltic andesite porphyry and 5.67 ± 0.07 Ma for the post-mineralization basaltic andesite cover. The high-precision CA-ID-TIMS analysis of the youngest grains from both rock types defines ages 5.778 ± 0.013 Ma and 5.700 ± 0.019, respectively, which bracket the ore mineralization between 5.791 and 5.681 Ma, including the error uncertainty. Consequently, the Öksüt gold mineralization took place in a very narrow lifetime of 78 ± 32 Ka. This is the youngest age for an economic gold deposit in Turkey.

Stages of Carboniferous-Triassic magmatism in the Black Sea region based on isotope-geochronological study of detrital zircons from jurassic coarse clastic strata of the Mountainous Crimea

The article presents the results of U-Pb isotope dating of detrital zircons from the Jurassic coarse rocks in the apex and the western slope of Mnt. Biyuk-Sinor (the southern wall of the Baidar basin, near the village of Orlinoe). These dates are compared with the detrital zircon dates obtained for sandy rocks from the Upper Jurassic coarse clastic strata composing the slopes of Mnt. Spilia near Balaklava Harbor and Mnt. Southern Demerdzhi near Alushta city, as well as the Middle Jurassic Bitak conglomerates near the village of Strogonovka (suburb of Simferopol city). The comparison shows a high degree of similarity of the averaged age characteristics of the main detrital zircon populations. Sandy rocks of Jurassic coarse clastic strata for zircon dating were sampled in four locations of the Mountaineous Crimea. Based on their dates and a summary set of ages of detrital zircon grains from sandstones of the Southern Coast of Crimea, spanning the stratigraphic interval from the Middle Jurassic to Neogene, we can provide a statistically reliable specification of the Carboniferous-Triassic time interval (360–200 Ma) of magmatic activity within the Black Sea region. This period was bounded in time by the Late Devonian and Early Jurassic relative magmatic lulls. None of the zircon grains of the Carboniferous-Triassic age has revealed Hf-isotopic characteristics indicating any significant contribution of crustal material older than the Mesoproterozoic into the protolith of the parent zircon rocks. Within the Carboniferous-Triassic interval of magmatic activity, three stages are distinguished: (I) 360–315 Ma, (II) 315–270 Ma, and (III) 270–200 Ma. Magmatic stage I (360–315 Ma) is related to the closure of the Reik ocean, which completed after the subducted slab ‘broke off’ into the mantle and was accompanied by the ubiquitously manifested HT-LP metamorphism. Zircon grains of stage I are characterized by peak ages of about 325–340 Ma and the dominance of negative εHf. Magmatic stages II (315–270 Ma) and III (270–200 Ma) correlate with functioning of the Scythian-Pontian volcanic suprasubduction belt. In these magmatic stages, zircon εHf values scatter from weakly negative to substantially positive (referred to the depleted mantle), which is typical for volcanic arcs. Fuzzy separation of stages II and III and strong variability of the peak ages of zircons from the studied samples (which we associate with these stages) can be due both to changes in magmatic activity in different segments of the belt, and to changes in the erosion intensity of crystalline complexes of the belt during the subsequent stages evolution caused by tectonic rearrangements within the Paleo-Tethys ocean and its peri-oceanic structures.

A New Two‐Step Strategy for Encapsulating Amorphous Polymer Chains in Thiourea Crystals

AbstractThe establishment of methodologies for encapsulating polymers in small molecular hosts is not only highly desirable to facilitate new material functions but also very important for the development of fundamental science. Herein a new strategy for encapsulating noncrystalline polymer chains with bulky side groups in thiourea (TU) crystals is disclosed. In the process, the noncrystalline polymer is first complexed with TU and 1,4‐dioxane molecules, forming a crystalline metastable complex structure with melting temperature below 110 °C. Subsequent removal of 1,4‐dioxane through heating the complex at 120 °C collapses the metastable complexes, but surprisingly affords a polymer‐TU inclusion compound (IC) structure, as demonstrated by infrared radiation, differential scanning calorimetry, and X‐ray powder diffraction. The strategy is applicable to both atactic‐poly (methyl methacrylate) and ‐polystyrene, suggesting that it might be a universal method for encapsulating noncrystalline polymer chains in thiourea crystal canals.

New insight into the interactions among starch, lipid and protein in model systems with different starches

The interactions of four starches-waxy maize starch (WMS), non-waxy maize starch (MS), potato starch (PS), wheat starch (WS)-with lauric acid (LA) and β-lactoglobulin (βLG) were investigated. Analysis of mixtures in the Rapid Visco Analyser (RVA) showed that the MS-LA and WS-LA systems presented a viscosity peak during the cooling and holding stages of the profile, PS-LA system showed only an increase in the final viscosity, whereas WMS-LA system displayed no obvious changes during the RVA cooling and holding stages. Structural analyses showed that wheat and maize starches formed more crystalline complexes with LA than potato starch, whereas no complexes were formed between WMS and LA. The addition of βLG increased the final viscosity of all starch-LA systems, with the most obvious increase observed for PS-LA systems. Structural analyses showed that the addition of βLG promoted the formation of starch-LA complexes, even for the WMS-LA system. From this study, it can be concluded that the nature of the starch affects the formation of starch-lipid complexes, and that these effects can be modified by βLG, which promotes the formation of starch-lipid complexes.

Synthesis and Structure of Tetra(para-tolyl)antimony Dicyanodiiodoaurate [p-Tol4Sb][Au(CN)2I2] and Alkyltriphenylphosphonium Dicyanodiiodoaurates [Ph3PAlk][Au(CN)2I2], Alk = Me, CH2CN

Red-colored crystalline gold complexes [p-Tol4Sb][Au(CN)2I2] (I), [Ph3PMe][Au(CN)2I2] (II), and [Ph3PCH2CN][Au(CN)2I2] (III) were synthesized by the reaction of potassium dicyanodiiodoaurate with tetra(para-tolyl)antimony and alkyltriphenylphosphonium halides in water. The structure of the complexes was established by IR and NMR spectroscopy and X-ray diffraction. The tetra(para-tolyl)antimony and alkyltriphenylphosphonium cations have a distorted tetrahedral coordination. The dicyanodiiodoaurate anions have a planar structure with a square coordination of the gold atom. The formation of the 3D crystal network is due to weak CN⋅⋅⋅H−C hydrogen bonds between cations and anions (2.39, 2.59 A (I), 2.70, 2.48, 2.52, 2.68 A (II), 2.73, 2.50, 2.67, 2.44 A (III)). In complex III, anions of one of the two types interact with one another via I⋅⋅⋅I contacts to give 1D ladder-like chains along the crystallographic a axis.

Interactions between dipfluzine-based complexes and cytochrome P450 enzymes: Information on salt, cocrystal, and salt cocrystal complexes

In the new drugs, greater than 90 % of active pharmaceutical ingredients (APIs) or marketed drugs have poor solubility and bioavailability, which restrict the development of pharmaceutical preparations. The use of crystalline molecular complexes (CMCs) involving API and biocompatible precursors to improve solubility has become a shortcut for new drug development. Most of the new drugs registered in CMC form are from postmarketing drugs, and the interaction between these drugs and cytochrome P-450 (CYP) enzymes is well documented. However, it is unclear whether the interactions between CMCs of postmarketing drugs and CYP enzymes should be re-evaluated. To clarify this problem, three dipfluzine (Dip)-based CMCs, including Dip-benzoic acid (BA) cocrystal, Dip-2-hydroxybenzoate (2HB) salt and Dip-4-hydroxybenzoate (4HB) salt-cocrystal, were chosen to investigate the interaction with CYP enzymes. Metabolites of Dip-based CMCs and cocktail probe drugs were measured via LC–MS/MS in the incubation reaction system comprising recombinant CYP enzymes (rCYPs) and human liver microsomes. Dip-based CMCs not only alter Dip-mediated inhibition or activation of CYP enzymes but also change the degree to which rCYPs are involved in Dip metabolism. Specifically, the inhibitory effects of Dip and Dip-HCl were increased compared with Dip-BA and Dip-2HB for CYP1A2; Dip-BA, Dip-2HB and Dip-4HB for CYP3A4; and Dip-BA for CYP2E1. The inhibitory effects of Dip and Dip-HCl were reduced compared with Dip-2HB and Dip-4HB for CYP2C19 and Dip-4HB for CYP2E1. The effects of the alterations of Dip CMCs on the interaction between Dip and CYP enzymes are not attributed to a simple superposition of Dip and the respective precursor and may be due to the presence of interaction forces between Dip and precursor molecules. These results are the first to provide preliminary experimental evidence that CMCs change the interaction between API and CYP enzymes. Moreover, these results further suggest the importance of re-evaluating interactions with CYP enzymes when CMC strategies are used to design new drugs and even for CMCs of postmarketing drugs with known metabolic characteristics.

On the origin of matrix mechanism in protocells and key problems of molecular biology

The theory of the emergence of the matrix mechanism in protocells on complexes of minerals (apatite, carbonate-apatite, calcite, and quartz) with the reciprocal proportions and with the participation of the gas phase radicals (NH3, CH4, and CO) is considered. The structure of apatite and carbonate-apatite predetermined the formation of a double helix of DNA with the complementary pairs of purine-pyrimidine bases, as well as RNA strands complementary to DNA, and helical protein chains combined into supramolecular structures with RNA. It is proposed that during the Archean Eon, a gradual replacement of the mineral matrix with organic matter took place. The site of the origin of the matrix mechanism is the defect-free and growing defective zone of apatite and carbonate-apatite. The size and specificity of DNA, complementary-bound RNA and protein molecules in supramolecular protein-RNA complexes increased as defects accumulated in the structure of minerals. An increase in the size of RNA transcripts was accompanied by an increase in the number of protein molecules in supramolecular protein-RNA complexes. At the first, anhydrous, stage, the formation of a transcriptional-translational apparatus in the form of a crystalline organic-mineral complex -DNA, RNA and protein, based on the “spiral into spiral” principle of gas phase elements. The appearance of water determined the launch of the transcriptional-translational apparatus and the transformation of the organo-mineral crystalline complex into a liquid-crystalline state. A detailed description of the preparation and launch of the matrix mechanism is given. The following problems are discussed: the origin of ribosomal proteins and the role of super-specific aminoacyl-tRNA synthetase as a true carrier of genetic information; properties of the genetic code and synthesis of protocells without violating the second law of thermodynamics; the origin of biological asymmetry; the appearance of nanobacteria and dark genetic matter of eukaryotic systems. Communicated by Ramaswamy H. Sarma

Effect of chemical structure on complexation efficiency of aromatic drugs with cyclodextrins: The example of dibenzazepine derivatives

It is widely believed that the hydrophobic effect governs the binding of guest molecules to cyclodextrins (CDs). However, it is also known that high hydrophobicity of guest molecules does not always translate to the formation of stable inclusion complexes with CDs. Indeed, a plethora of other factors can play a role in the efficiency of guest–CD interactions, rendering structure-based prediction of the complexation efficiency with CDs a non trivial task. In this combined experimental and computational study, we examine the major structural factors governing complexation efficiency of polycyclic aromatic drug-like compounds with natural CDs, using as an example iminostilbene and its N-substituted derivatives. We find that purely hydrophobic IS derivatives show negligible complexation efficiency with CDs and only IS with hydrophilic substituents form stable inclusion complexes in water. We show that the balance between the guest solubility and its affinity to CDs is critical for the effective formation of inclusion complexes. Finally, our results demonstrate that guest–host hydrogen bonds facilitate the formation of crystalline inclusion complexes with CDs.

Influence of hydrogen bond on the mesomorphic behaviour in urethane based liquid crystalline compounds: Experimental and computer simulation study

We present a combined experimental and theoretical study on the novel hydrogen-bonded liquid crystalline complex (UR-LC11) exhibiting both nematic and smectic phases upon cooling. The complex was prepared by mixing 2-(2-methoxyethoxy)ethylbutyl carbamate (UR) as H-bond acceptor with calamitic mesogen 4′-((11-hydroxyundecyl)oxy)-[1,1′-biphenyl]-4‑carbonitrile (LC11) as H-bond donor. The complex was characterized by FTIR technique and its liquid crystalline properties were studied by differential scanning calorimetry (DSC) and polarized optical microscope (POM). The experimental IR spectra were compared with theoretically obtained IR spectra by Density Functional Theory (DFT) to suggest the structure of hydrogen-bonded liquid crystal (LC). The molecular dynamics (MD) simulations were performed to understand the impact of hydrogen bonding on the mesomorphic behaviour of the complex and the temperature dependency of the transitions between the mesophases. We determined that UR-LC11 is a stable H-bond acceptor/donor type complex and a single H-bond forms between the carbonyl oxygen atom of the amide moiety of UR and the hydrogen atom of the terminal hydroxyl group of the LC11. Although LC11 is present only in nematic liquid crystalline form, the new complex displayed both nematic and smectic phases during cooling. The reason for the two distinctive LC phases was explained by the presence of hydrogen bond interactions, which provides structural flexibility. Besides, H-bond maintains uniaxial rod shape of the molecule to promote self-assembly behaviour and induces positional ordering in the smectic phase. The enhancement in the self-assembly of the H-bonded chains in the complex is reflected in the increased ΔHfusion values. Due to the intermolecular π-π interactions of the phenyl rings and the formation of strong dipoles on the backbone, especially at the cyanobiphenyl end of the chains, the long-range directional order of the dipoles along their long axes are preserved at elevated temperatures and nematic to isotropic phase transition is observed at around 370 K both experimentally and theoretically.

Quantitative Precipitation of Uranyl or Plutonyl Nitrate with N-(1-Adamantyl)acetamide in Nitric Acid Aqueous Solution.

The reactivity of the N-(1-adamantyl)acetamide ligand (L = adam) has been evaluated as precipitating agent for the hexavalent uranyl cation ([U] = 20-60 g L-1) in concentrated nitric acid aqueous solution (0.5-5 M). It results in the formation of a crystalline complex (UO2)(adam)2(NO3)2·2(adam) (1), in which the uranyl center is 8-fold coordinated to two chelating nitrate groups and two N-(1-adamantyl)acetamide (= adam) ligands through the oxygen atom of the amide function. Two other noncoordinating adam moieties are also observed in the crystal structure packing and interact through a hydrogen-bond scheme with the uranyl-centered species. A similar molecular assembly has been obtained with the plutonyl(VI) cation, in the complex (PuO2)(adam)2(NO3)2·2(adam) (2). Precipitation studies indicate high (UO2)(adam)2(NO3)2·2(adam) formation yields (up to 99%U for an L/U molecular ratio of 5/1) for HNO3 concentration in the 0.5-5 M range. However, the precipitation kinetics is rather slow and the reaction is completed after several hours (3-4 h). The calcination of the resulting solid under an air atmosphere led to the formation of the U3O8 oxide from 400 °C through a transient phase UO2 fluorite-type (from 200 °C).

Petrogenesis and Lu–Hf Dating of (Ultra)Mafic Rocks from the Kutná Hora Crystalline Complex: Implications for the Devonian Evolution of the Bohemian Massif

Abstract The Lu–Hf isotope system and Sr–Nd–Hf–Os isotope systematics of mantle rocks are capable of unravelling the early processes in collision belts, especially in a hot subduction context where the Sm–Nd and U–Pb systems in crustal rocks are prone to resetting owing to high temperatures and interaction with melts during exhumation. To improve models of the Devonian–Carboniferous evolution of the Bohemian Massif, we investigated in detail mafic and ultramafic rocks (eclogite, pyroxenite, and peridotite) from the ultrahigh-pressure and ultrahigh-temperature Kutná Hora Crystalline Complex (KHCC: Úhrov, Bečváry, Doubrava, and Spačice localities). Petrography, multiphase solid inclusions, major and trace element compositions of rocks and minerals, and radiogenic isotopic data document contrasting sources and protoliths as well as effects of subduction-related processes for these rocks. The Úhrov peridotite has a depleted composition corresponding to the suboceanic asthenospheric mantle, whereas Bečváry and Doubrava peridotites represent lithospheric mantle that underwent melt refertilization by basaltic and SiO2-undersaturated melts, respectively. Multiphase solid inclusions enclosed in garnet from Úhrov and Bečváry peridotites represent trapped H2O ± CO2-bearing metasomatizing agents and Fe–Ti-rich melts. The KHCC eclogites either formed by high-pressure crystal accumulation from mantle-derived basaltic melts (Úhrov) or represent a fragment of mid-ocean ridge basalt-like gabbroic cumulate (Spačice) and crustal-derived material (Doubrava) both metamorphosed at high P–T conditions. The Lu–Hf age of 395 ± 23 Ma obtained for the Úhrov peridotite reflects garnet growth related to burial of the asthenospheric mantle during subduction of the oceanic slab. By contrast, Spačice and Doubrava eclogites yield younger Lu–Hf ages of ∼350 and 330 Ma, respectively, representing mixed ages as demonstrated by the strong granulite-facies overprint and trace element zoning in garnet grains. We propose a refined model for the Early Variscan evolution of the Bohemian Massif starting with the subduction of the oceanic crust (Saxothuringian ocean) and associated oceanic asthenospheric mantle (Úhrov) beneath the Teplá–Barrandian at ≥380 Ma, which was responsible for melt refertilization of the associated mantle wedge (Bečváry, Doubrava). This was followed by continental subduction (∼370–360 Ma?) accompanied by the oceanic slab break-off and incorporation of the upwelling asthenospheric mantle into the Moldanubian lithospheric mantle and subsequent coeval exhumation of mantle and crustal rocks at ∼350–330 Ma.

New detrital zircon age data reveal the location of the Rheic suture in the Mid-German Crystalline Zone (Spessart and Odenwald Crystalline Complexes)

New detrital zircon age data of metasedimentary rocks from the Spessart and Odenwald basement (Mid-German Crystalline Zone, Variscides) revealed results, which are not compatible with current tectonic models. The previously proposed existence of a tectonic window, which includes lower plate Rhenohercynian rocks within the upper plate (Saxothuringian Zone) in the Spessart and Odenwald basement, does not agree with the results of this study. This leads to a new course of the Rheic suture and, therefore, a non-coherence of the two major fault zones in these complexes. The southern Spessart Crystalline Complex accommodates the Rheic suture, which is most likely explained by a southward displacement of a whole segment of the Mid-German Crystalline Zone. This displacement might extend over the Ruhla Crystalline Complex. A hitherto unknown age spectrum of a unit in the Bollsteiner Odenwald was found, which might indicate a sliver of unidentified material in the Variscan collision zone. An unknown magmatic age of 350 Ma is reported for igneous intrusions in the Saxothuringian Zone and can be used as an additional indicator to distinguish between Laurussia- and Gondwana-related rocks.

A novel AA10 from Paenibacillus curdlanolyticus and its synergistic action on crystalline and complex polysaccharides.

Lytic polysaccharide monooxygenases (LPMOs) play an important role in the degradation of complex polysaccharides in lignocellulosic biomass. In the present study, we characterized a modular LPMO (PcAA10A), consisting of a family 10 auxiliary activity of LPMO (AA10) catalytic domain, and non-catalytic domains including a family 5 carbohydrate-binding module, two fibronectin type-3 domains, and a family 3 carbohydrate-binding module from Paenibacillus curdlanolyticus B-6, which was expressed in a recombinant Escherichia coli. Comparison of activities between full-length PcAA10A and the catalytic domain polypeptide (PcAA10A_CD) indicates that the non-catalytic domains are important for the deconstruction of crystalline cellulose and complex polysaccharides contained in untreated lignocellulosic biomass. Interestingly, PcAA10A_CD acted not only on cellulose and chitin, but also on xylan, mannan, and xylan and cellulose contained in lignocellulosic biomass, which has not been reported for the AA10 family. Mutation of the key residues, Trp51 located at subsite - 2 and Phe171 located at subsite +2, in the substrate-binding site of PcAA10A_CD revealed that these residues are substantially involved in broad substrate specificity toward cellulose, xylan, and mannan, albeit with a low effect toward chitin. Furthermore, PcAA10A had a boosting effect on untreated corn hull degradation by P. curdlanolyticus B-6 endo-xylanase Xyn10D and Clostridium thermocellum endo-glucanase Cel9A. These results suggest that PcAA10A is a unique LPMO capable of cleaving and enhancing lignocellulosic biomass degradation, making it a good candidate for biotechnological applications. KEY POINTS: • PcAA10A is a novel modular LPMO family 10 from Paenibacillus curdlanolyticus. • PcAA10A showed broad substrate specificity on β-1,4 glycosidic linkage substrates. • Non-catalytic domains are important for degrading complex polysaccharides. • PcAA10A is a unique LPMO capable of enhancing lignocellulosic biomass degradation.

Development and evaluation of crystalline inclusion complex of finasteride using electrospraying as a novel approach

Solid form of drug plays the central role in optimizing its physicochemical properties, thus discovery of new solid forms always provides more options to achieve the desirable pharmaceutical profiles of drugs. Recently, certain drugs have been found to form crystalline inclusion complexes (ICs) with multiple types of linear polymers, representing a new sub-category of pharmaceutical solids. In this study, Finasteride (FNS) was used as the model host and poly (ethylene glycol) (PEG) as the guest, to form ICs of drug with the purpose of offering solubility advantage. Electrospraying as a novel approach was used for production of micro-particles of crystalline ICs of FNS, as it gave narrow particle size distribution and dry powder as end product. The obtained dry powder was characterized using powder X-ray diffraction, NMR spectroscopy and other characterization methods. The results revealed that FNS formed ICs with the biodegradable hydrophilic polymer (PEG), thus offering a FNS-PEG ICs as a potential new solid form. Compared with pure FNS crystals the FNS-PEG ICs crystals showed significantly higher solubility and faster dissolution rates; making it more suitable to achieve higher drug release profiles. Results demonstrated the possibility of using drug-polymer ICs microparticles as solid forms, providing a new approach to design formulations with enhanced drug release. In a nutshell developed formulation was found to be suitable for enhancing water solubility of poorly soluble actives.