ALBERT

Description: Abstract. The title compounds NH 4 [Cu(S 2 CNH 2 ) 2 ] · H 2 O (A) and CuS 2 CNH 2 (B) were prepared from aqueous alcoholic solutions by reaction of ammoniumdithiocarbamate with copper sulfate in presence of excess cyanide as reductive. (A) crystallizes in the orthorhombic space group C 222 1 (No. 20) with a = 8.9518(6), b = 9.6414(6) and c = 10.6176(8) Å, Z = 4. (B) crystallizes in the orthorhombic space group P 2 1 2 1 2 1 (No. 19) with a = 5.9533(4), b = 6.6276(4) and c = 9.4834(5) Å, Z = 4. In the crystal structure of (A) copper has a tetrahedral surrounding of four monodentate dithiocarbamate ligands. These structural units form 2D nets stacked along [001]. Staggered chains consisting of H 2 O and NH 4 + penetrate the crystal structure along [001] yielding additional coherence via hydrogen bonds. The crystal structure of (B) comprises a three-dimensional tetrahedral framework of CuS 4 units exclusively linked by vertices. The arrangement is reminiscent of a filled β -cristobalite structure with the dithiocarbamate ligands extending into the hollow spaces. Thermal decomposition precedes stepwise finally giving Cu 2 S in each case.

Description: The title compound AgS 2 CN R 2 was prepared from an aqueous alcoholic solution by reaction of dicyanoargentate [Ag(CN) 2 ] – with excess ammoniumdithiocarbamate. It crystallizes in the tetragonal space group I 2 d (No. 122) with a = 7.9898(4) and c = 12.1072(7) Å, V = 772.89(7) Å 3 , Z = 8. The crystal structure comprises a 3D tetrahedral network of distorted AgS 4 units connected via all vertices thus forming the β-cristobalite structure type. The dithiocarbaramate ligands extend into the hollow space of the framework. Thermal decomposition starts above 125 °C and proceeds with a complex reaction to give finally Ag 2 S (acanthite).

Description: Scarab blue crystals of the title compound were precipitated from aqueous solutions of Cr III salts by adding an excess of ammoniumdithiocarbamate solution. The compound crystallizes in the trigonal space group R (No. 148) with a = 13.2694(8), c = 11.2542(7) Å and γ = 120°. The crystal structure consists of a three-dimensional hydrogen-bonded network of six Cr(S 2 CNH 2 ) 3 molecules per unit cell. The CrS 6 polyhedron is twisted with trigonal antiprismatic arrangement and approximate D 3 symmetry. Thermal decomposition starts at T ≈ 185 °C followed by several simultaneous decomposition reactions. The residue is a mixture of Cr 2 S 3 and deficient sulfur chromium sulfides.

Description: The title compounds were prepared from aqueous alcoholic solutions by reaction of ammoniumdithiocarbamate with bismuth trichloride. NH 4 Bi(S 2 CNH 2 ) 4 ·H 2 O crystallises in the monoclinic space group P 2 1 / c (No. 14) with a = 8.4109(17), b = 13.198(3) and c = 16.678(3) Å, β = 97.17(3)°and Bi(S 2 CNH 2 ) 3 crystallises in the triclinic space group P (No. 2) with a = 5.8951(5), b = 8.3026(7), c = 12.5030(10) Å, α = 103.460(10), β = 95.080(10) and γ = 91.330(10) °. The crystal structure of NH 4 Bi(S 2 CNH 2 ) 4 ·H 2 O comprises isolated polyhedrons around bismuth (eightfold coordination) linked by hydrogen bonds originating from ammonium, the co-crystallised water and the dithiocarbamate. In the crystal structure of Bi(S 2 CNH 2 ) 3 exist dimeric aggregates comprising two distorted square antiprisms around bismuth, which are linked together by a common edge. They form infinite double chains with composition [Bi 2 (S 2 CNH 2 ) 6 ] ∞ , which are bridged by N–H···S hydrogen bonds. Evaluation of differential thermal analysis data shows that Bi 2 S 3 develops in the temperature range between 125 and 150 °C, whereas mainly gaseous NH 3 and CS 2 are emitted during the decomposition reaction.

Description: Abstract Increasing glacial discharge can lower salinity and alter organic matter (OM) supply in fjords, but assessing the biogeochemical effects of enhanced freshwater fluxes requires understanding of microbial interactions with OM across salinity gradients. Here, we examined microbial enzymatic capabilities—in bulk waters (nonsize‐fractionated) and on particles (≥ 1.6 μm)—to hydrolyze common OM constituents (peptides, glucose, polysaccharides) along a freshwater–marine continuum within Tyrolerfjord‐Young Sound. Bulk peptidase activities were up to 15‐fold higher in the fjord than in glacial rivers, whereas bulk glucosidase activities in rivers were twofold greater, despite fourfold lower cell counts. Particle‐associated glucosidase activities showed similar trends by salinity, but particle‐associated peptidase activities were up to fivefold higher—or, for several peptidases, only detectable—in the fjord. Bulk polysaccharide hydrolase activities also exhibited freshwater–marine contrasts: xylan hydrolysis rates were fivefold higher in rivers, while chondroitin hydrolysis rates were 30‐fold greater in the fjord. Contrasting enzymatic patterns paralleled variations in bacterial community structure, with most robust compositional shifts in river‐to‐fjord transitions, signifying a taxonomic and genetic basis for functional differences in freshwater and marine waters. However, distinct dissolved organic matter (DOM) pools across the salinity gradient, as well as a positive relationship between several enzymatic activities and DOM compounds, indicate that DOM supply exerts a more proximate control on microbial activities. Thus, differing microbial enzymatic capabilities, community structure, and DOM composition—interwoven with salinity and water mass origins—suggest that increased meltwater may alter OM retention and processing in fjords, changing the pool of OM supplied to coastal Arctic microbial communities.

Description: The gut hormone ghrelin is involved in numerous metabolic functions, such as the stimulation of growth hormone secretion, gastric motility, and food intake. Ghrelin is modified by ghrelin O-acyltransferase ( GOAT) or membrane-bound O-acyltransferase domain-containing 4 ( MBOAT4 ) enabling action through the growth hormone secretagogue receptors ( GHS-R ). During the course of evolution, initially strong ligand/receptor specificities can be disrupted by genomic changes, potentially modifying physiological roles of the ligand/receptor system. Here, we investigated the coevolution of ghrelin, GOAT, and GHS-R in vertebrates. We combined similarity search, conserved synteny analyses, phylogenetic reconstructions, and protein structure comparisons to reconstruct the evolutionary history of the ghrelin system. Ghrelin remained a single-gene locus in all vertebrate species, and accordingly, a single GHS-R isoform was identified in all tetrapods. Similar patterns of the nonsynonymous ( dN ) and synonymous ( dS ) ratio ( dN/dS ) in the vertebrate lineage strongly suggest coevolution of the ghrelin and GHS-R genes, supporting specific functional interactions and common physiological pathways. The selection profiles do not allow confirmation as to whether ghrelin binds specifically to GOAT , but the ghrelin dN/dS patterns are more similar to those of GOAT compared to MBOAT1 and MBOAT2 isoforms. Four GHS-R isoforms were identified in teleost genomes. This diversification of GHS-R resulted from successive rounds of duplications, some of which remained specific to the teleost lineage. Coevolution signals are lost in teleosts, presumably due to the diversification of GHS-R but not the ghrelin gene. The identification of the GHS-R diversity in teleosts provides a molecular basis for comparative studies on ghrelin's physiological roles and regulation, while the comparative sequence and structure analyses will assist translational medicine to determine structure–function relationships of the ghrelin/ GHS-R system. We investigated the coevolution of ghrelin, GOAT , and GHS - R s, and we found similar patterns of selection profiles in amphibian, reptiles, and birds, which strongly suggest coevolution of ghrelin and GHS - R genes, supporting specific functional interaction and common physiological pathways. By contrast, coevolution signals are lost in teleosts, presumably due to the diversification of GHS - R s. Our results allowed to clarify the evolutionary history of ghrelin receptors and provide further insights into studies on structure–function relationships, also allowing to mechanistically understand and presumably therapeutically target the ghrelin/ GHS - R system.

Description: The title compound AuS 2 CNH 2 was prepared from an aqueous solution by reaction of dicyanidoaurate [Au(CN) 2 ] – with excess of ammoniumdithiocarbamate NH 4 S 2 CN H 2 at pH ≈ 2. The compound crystallizes in the orthorhombic space group Cmma with a = 6.4597(2), b = 12.6556(3), and c = 5.3235(1) Å. The crystal structure comprises linear S–Au–S dumbbells forming unbranched zigzag chains in combination with the dithiocarbamate ligands. The three-dimensional arrangement of the molecules is realized by aurophilic Au I –Au I and hydrogen bonding interactions, respectively. AuS 2 CNH 2 presents orange luminescence due to a broad emission band between 12000 cm –1 and 23000 cm –1 (ν = 26316 cm –1 ).

Description: [Sn(S 2 CNH 2 ) 2 S] 2 · 2H 2 O · EtOH ( A ) was prepared via oxidation of Sn 2+ with thiuram sulfide in aqueous alcohol solution. The compound [Sn(S 2 CNH 2 ) 2 S] 2 · 4EtOH ( B ) crystallizes from a saturated alcoholic solution of A . The monoclinic unit cell of A , space group P 2 1 / n (No. 14), a = 12.9169(9), b = 9.7222(5), c = 19.504(12) Å and β = 99.802(8) °, contains four formula units. B crystallizes in the orthorhombic space group Fddd (No. 70), a = 12.9500(4), b = 13.7737(4), c = 34.6012(12) Å with Z = 8 formula units per unit cell. The crystal structures consist of dinuclear Sn(S 2 CNH 2 ) 2 units doubly bridged by two sulfide (S 2– ) anions forming a centrosymmetric Sn 2 S 2 square. These units are interlaced by primarily strong hydrogen bonds originating from the solvate molecules and the amino groups (O–H ··· S, N–H ··· O and N–H ··· S for A and N–H ··· O and O–H ··· S for B ). The two solvate crystals can be interconverted via their alcoholic solution. B recrystallizes after saturation and A precipitates if a suitable portion of water is added.

Description: Strong feedbacks exist between channel dynamics, floodplain development and riparian vegetation. Earlier experimental studies showed how uniformly distributed riparian vegetation causes a shift from a braided to a single-thread river because riparian vegetation stabilizes the banks and focuses discharge off the floodplains into channels. These experiments tested anemochorously distributed vegetation, i.e., by wind, whereas many riparian species in nature are also distributed hydrochorously, i.e., by flowing water. The objective of this study is to test experimentally what the different effects are of hydrochorously and anemochorously distributed vegetation on channel pattern and dynamics. The experiments were carried out in a flume of 3 m wide and 10 m long. We compared experiments with the two forms of vegetation distribution methods to control experiments without vegetation. To independently quantify bank retreat rate as a function of seed density and vegetation age, we used a small bank erosion test. In agreement with other work, the uniformly distributed vegetation decreased bank retreat, often stabilized banks and tightened meander bends. Vegetation seeds distributed by the flow during floods settled at lower elevations compared to the uniformly distributed vegetation. Inner bend vegetation stabilized a part of the point bar and hydraulic resistance of the vegetated bar forced water into the channel and over the floodplain. As a result, sediment was deposited upstream of vegetation patches. We conclude that seeds distributed by the flow during floods lead to island braiding: a patchy multi-thread river with stable vegetated bars, whereas vegetation uniformly distributed on the floodplain of a single-thread meandering river increases sinuosity and decreases bend wavelength. This implies that the combination of discharge variations and vegetation settling behavior has a large effect on the morphology and dynamics of rivers. The experimental approach opens up a wide range of possibilities to explore hydrobio-geomorphological interactions with a high degree of control.

Description: Bisphenols, anthropogenic pollutants, leach from consumer products and have potential to be ingested and are excreted in waste. The endocrine disrupting effects of highly manufactured bisphenols (BPA, BPS, and BPF) are known, however the activities of others are not. Here, the estrogenic and androgenic activities of a series of 4,4'-bisphenols that vary at the inter-connecting bisphenol bridge were determined (BPA, BPB, BPBP, BPC2, BPE, BPF, BPS, and BPZ) and compared to in silico binding to estrogen receptor-alpha and the androgen receptor. Bioassay results showed the order of estrogenicity (BPC2 (strongest) 〉 BPBP 〉 BPB 〉 BPZ 〉 BPE 〉 BPF 〉 BPA 〉 BPS, r 2  = 0.995) and anti-androgenicity (BPC2 (strongest) 〉 BPE, BPB, BPA, BPF, and BPS, r 2  = 0.996) correlated to nuclear receptor binding affinities. Like testosterone and the anti-androgen hydroxyflutamide, bisphenol fit in the ligand-binding domain through hydrogen-bonding at residues Thr877 and Asn705, but also interacted at either Cys784/Ser778 or Gln711 through the other phenol ring. This suggests the 4,4'-bisphenols, like hydroxyflutamide, are androgen receptor antagonists. Hydrogen-bond trends between ERα and the 4,4'-bisphenols were limited to residue Glu353, which interacted with the –OH of one phenol and the –OH of the A ring of 17β-estradiol; hydrogen-bonding varied at the –OH of ring D of 17β-estradiol and the second phenol –OH group. While both estrogen and androgen bioassays correlated to in silico results, conservation of hydrogen-bonding residues in the androgen receptor provides a convincing picture of direct antagonist binding by 4,4'-bisphenols.