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The use of a grapevine-shoot extract (VIN) is being studied as an alternative to sulfur dioxide (SO2 ). VIN stabilizes anthocyanins and preserves polyphenolic compounds, and thus improves chromatic wine properties. In this study, selected aroma compounds (esters, C13 -norisoprenoids, oxidation and vine-shoot-related compounds), sensory analysis and the olfactometric profile were determined in the wines treated with VIN at two concentrations.; Results: Treatment with VIN hardly modified the content of esters and oxidation-related compounds in the wines. However, the high β-damascenone and isoeugenol contents and the increase in astringency at tasting in VIN wines were noteworthy, as were some odorant zones. All these were established as VIN markers after the chemometric data analysis.; Conclusion: These data revealed that only the lowest dose tested may be recommended as a suitable alternative to SO2 . Although some aromatic properties of these wines may change, these changes are not considered to affect the quality of the wines negatively. These results are useful for wineries, which face having to discover the aroma-related processes in the challenge of producing SO2 -free wines without detriment to their sensory properties. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

The reaction of [TaCp*Me3(OTf)] with chelidamic acid yields the carboxylate derivative [TaCp*Me(OTf)((OOC)2py(OH)-κ3-O,N,O)] (1) that reacts with water to yield the cationic dimetallic complex [{TaCp*((OOC)2py(OH)-κ3-O,N,O)}2(μ2-OH)3](OTf) (2). In an analogous procedure, the reaction of [TaCp*Me3(OTf)] with diglycolic acid renders the triflate compound [TaCp*Me{(OOCCH2)2O}-κ3-O,O,O)(OTf)] (4). Citric acid (CITH4) reacts with [TaCp*Me4] and water to give the dimetallic complex [{TaCp*(CITH)(OH2)}(μ-O){TaCp*(CITH2)(OH)}] (6). Compound [TaCp*Me3(OTf)] reacts with an excess of water in CH2Cl2 to give the trimetallic tantalum hydroxide [{TaCp*(OH)(OH2)}3(μ3-OH)(μ2-O)3](OTf)2 (7). Complexes 2, 6 and 7 have been studied by X-ray diffraction.

In this paper we analyse how external social capital affects innovativeness through knowledge acquisition. Specifically, we test the effect of density, trust and cognitive proximity on the innovativeness of firms and the mediating role of external knowledge acquisition to explain these relationships. We focus our empirical study upon the footwear industry in Spain, using partial least squares to test the proposed hypotheses. The main contribution of this study is to demonstrate how knowledge acquisition leads the firm's external social capital to innovativeness.

The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbred populations, and little is known about these phenomena in endangered populations. Most researchers conclude that the relation between coefficient of inbreeding estimated from pedigrees and fitness traits (inbreeding-fitness correlations) better reflects inbreeding depression than the relation between marker heterozygosity and fitness traits (heterozygosity-fitness correlations). However, it has been suggested recently that heterozygosity-fitness correlations should only be expected when inbreeding generates extensive identity disequilibrium (correlations in heterozygosity and homozygosity across loci throughout the genome). We tested this hypothesis in Mohor gazelle (Gazella dama mhorr) and Iberian lynx (Lynx pardinus). For Mohor gazelle, we calculated the inbreeding coefficient and measured heterozygosity at 17 microsatellite loci. For Iberian lynx, we measured heterozygosity at 36 microsatellite loci. In both species we estimated semen quality, a phenotypic trait directly related to fitness that is controlled by many loci and is affected by inbreeding depression. Both species showed evidence of extensive identity disequilibrium, and in both species heterozygosity was associated with semen quality. In the Iberian lynx the low proportion of normal sperm associated with low levels of heterozygosity was so extreme that it is likely to limit the fertility of males. In Mohor gazelle, although heterozygosity was associated with semen quality, inbreeding coefficient was not. This result suggests that when coefficient of inbreeding is calculated on the basis of a genealogy that begins after a long history of inbreeding, the coefficient of inbreeding fails to capture previous demographic information because it is a poor estimator of accumulated individual inbreeding. We conclude that among highly endangered species with extensive identity disequilibrium, examination of heterozygosity-fitness correlations may be an effective way to detect inbreeding depression, whereas inbreeding-fitness correlations may be poor indicators of inbreeding depression if the pedigree does not accurately reflect the history of inbreeding.

Tantalum complexes [TaCp*Me{κ(4)-C,N,O,O-(OCH(2))(OCHC(CH(2)NMe(2))=CH)py}] (4) and [TaCp*Me{κ(4)-C,N,O,O-(OCH(2))(OCHC(CH(2)NH(2))=CH)py}] (5), which contain modified alkoxide pincer ligands, were synthesized from the reactions of [TaCp*Me{κ(3)-N,O,O-(OCH(2))(OCH)py}] (Cp* = η(5)-C(5)Me(5)) with HC≡CCH(2)NMe(2) and HC≡CCH(2)NH(2), respectively. The reactions of [TaCp*Me{κ(4)-C,N,O,O-(OCH(2))(OCHC(Ph)=CH)py}] (2) and [TaCp*Me{κ(4)-C,N,O,O-(OCH(2))(OCHC(SiMe(3))=CH)py}] (3) with triflic acid (1:2 molar ratio) rendered the corresponding bis-triflate derivatives [TaCp*(OTf)(2){κ(3)-N,O,O-(OCH(2))(OCHC(Ph)=CH(2))py}] (6) and [TaCp*(OTf)(2){κ(3)-N,O,O-(OCH(2))(OCHC(SiMe(3))=CH(2))py}] (7), respectively. Complex 4 reacted with triflic acid in a 1:2 molar ratio to selectively yield the water-soluble cationic complex [TaCp*(OTf){κ(4)-C,N,O,O-(OCH(2))(OCHC(CH(2)NHMe(2))=CH)py}]OTf (8). Compound 8 reacted with water to afford the hydrolyzed complex [TaCp*(OH)(H(2)O){κ(3)-N,O,O-(OCH(2))(OCHC(CH(2)NHMe(2))=CH(2))py}](OTf)(2) (9). Protonation of compound 8 with triflic acid gave the new tantalum compound [TaCp*(OTf){κ(4)-C,N,O,O-(OCH(2))(HOCHC(CH(2)NHMe(2))=CH)py}](OTf)(2) (10), which afforded the corresponding protonolysis derivative [TaCp*(OTf)(2){κ(3)-N,O,O-(OCH(2))(HOCHC(CH(2)NHMe(2))=CH(2))py}](OTf) (11) in solution. Complex 8 reacted with CNtBu and potassium 2-isocyanoacetate to give the corresponding iminoacyl derivatives 12 and 13, respectively. The molecular structures of complexes 5, 7, and 10 were established by single-crystal X-ray diffraction studies.

To better understand the role of the non-canonical Notch ligand delta-like protein 1 (DLK1), in hormone-producing cells, we studied the cell distribution and subcellular localisation of DLK1 in the pituitary of male adult 129/SvJ mice, and analysed the variations in the hormone-producing cells associated with the lack of this gene in Dlk1 knockout mice. The results obtained showed the presence of DLK1-immunoreactive (ir) cells in all hormone-producing cells of the anterior pituitary. Immunoelectron microscopy showed DLK1-ir in the rough endoplasmic reticulum and inside secretory vesicles, suggesting that DLK1 is released together with pituitary hormones. Moreover, we found that prolactin (PRL)-DLK1-ir cells are in intimate contact with follicle-stimulating hormone (FSH)-ir-DLK1-negative cells. In Dlk1 knockout mice, we detected a significantly lower number of gowth hormone (GH)-ir cells, a reduction in the FSH and PRL immunostaining intensity, and a significant decrease in FSH mRNA expression compared to wild-type mice. An increase in pituitary GH mRNA expression and serum leptin levels was also found. These findings provide evidence supporting several regulatory functions of DLK1 in the pituitary gland.

New monocyclopentadienyl species of TaV, [Cp*TaL3(XR)] (L = Cl, Me, X = O, S) bearing 4,6-dimethyl-2-pyrimidinethiolate (SR = SC6H7N2) or 3-cyano-4,6-dimethyloxypyridine (OR = OC8H7N2) ligands were prepared, namely [Cp*TaCl3(SC6H7N2)] (1), [Cp*TaCl3(OC8H7N2)] (2), [Cp*TaMe3(SC6H7N2)] (3). In addition, a bis(oxypyridine)titanium(IV) complex [Cp*TiMe2(OC8H7N2)2] was isolated. The X-ray structure analysis of 1 revealed that the thiolate group is bonded to the metal center through the sulfur atom and one of the nitrogen atoms in an η2-fashion. The reactivity of complex 3 with isocyanides (CNR), R = tBu, Xyl (Xyl = 2,6-dimethylphenyl) was also studied showing differences depending on the nature of R group. The reaction with 2,6-dimethylphenyl isocyanide gives the azatantalacyclobutane complex [Cp*TaMe{XylN=CC(Me2)NXyl}(SC6H7N2)] (5) as the final product, whereas in the reaction with tert-butyl isocyanide the η2-imine-containing complex [Cp*Ta{tBuNC(Me2)}(SC6H7N2)] (6) is proposed to be formed. The dynamic behavior of [Cp*TaMe3(SC6H7N2)] (3) was also studied by variable-temperature 1H NMR spectroscopy. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

© 2017 The Authors., With the aim of studying delta‐like protein 1 (DLK1) with respect to the relationship between adipocyte leptin and adenohypophyseal hormones, we carried out an immunohistochemical study analysing the presence of receptors for these hormones in the pituitary and adipose cells of male wild‐type (WT) mice (Dlk1+/+) compared to knockout (KO) mice (Dlk1−/−). The mRNA expression of these molecules was also determined using the reverse transcriptase‐polymerase chain reaction. The results obtained showed that, in WT adipose cells, all of the adenohypophyseal hormone receptors were present, with a higher mRNA expression for growth hormone (GH) receptor and thyroid‐stimulating hormone (TSH) receptor. Of the total cells in the anterior pituitary lobe, 17.09±0.9% were leptin receptor (LEPR) immunoreactive (‐IR), mainly in GH‐IR and prolactin (PRL)‐IR cells (41.5±3.8%; 13.5±1.7%, respectively). In Dlk1−/− mice, adipocyte cells showed a significant increase in the TSH receptor mRNA expression level. Moreover, the percentage of LEPR‐IR GH cells showed a statistically significant increase compared to controls, from 41.5±3.8% to 53.1±4.0%. By contrast, only 3.0±0.6% of LEP‐IR anterior pituitary cells were detected in Dlk1 KO mice, as opposed to 6.8±1.1% observed in WT mice. The results suggest that relationships exist between adipocytes and pituitary GH, PRL and TSH cells, in addition to an influence with respect to the synthesis and release of pituitary leptin, particularly in PRL cells., Support was provided by the Consejería de Ciencia y Tecnología JCCM (grants PAI06‐0066‐6930 and PII1I09‐0065‐8194 to C. Díaz).

Rhodium supported on titania-silica is modeled by 1, which was obtained from [{Cp*TiMe(μ-O2 SiPh2 )}2 ] (2) and [{Rh(OH)(cod)}2 ]. Complex 2 and its triply bridged derivative [Cp*Ti(μ-O2 SiPh2 )3 TiCp*] (3) can be envisaged as molecular models of titania-silica systems. Compounds 1-3 could potentially provide insights into the nature of the catalytically active sites in these systems; cod=1,5-cycloctadiene, Cp*=η5 -C5 Me5 .

The wild-type of the filamentous fungus Mucor circinelloides accumulates the yellow pigment β-carotene. At a continuous blue-light fluence rate of 0.1 W/m2 the β-carotene content increases about eight fold over the dark controls. Among the mutants isolated after exposure of spores to either N-methyl-N'-nitro-N-nitrosoguanidine or ICR-170, a red mutant accumulating lycopene, white mutants accumulating phytoene and white mutants without carotenoids were found. The biosynthesis of carotenoids in M. circinelloides shows similarities with that of the fungus Phycomyces blakesleeanus such as the presence of mutants in the same structural genes and the induction by light of the pathway. However, negative end-product regulation by β-carotene on the biosynthetic pathway, as in Phycomyces, is absent in M. circinelloides. In contrast to Phycomyces carB and carR mutants, carotenoids in corresponding mutants of M. circinelloides are photoinduced.

The first enantiospecific synthesis of 2 , a phosphonate isostere of phosphothreonine suitably protected for solid-phase peptide synthesis, has been achieved by coupling the highly face-selective conjugate addition of the lithium salt of Schollkopf's bislactim ether to E -prop-2-enyl-phosphonates with a selective enzymatic carboxylic ester hydrolysis. The absolute configuration of the products has been assigned from the X-ray structure of the adduct 9c .

Optically pure (+)-elsaminose ( 2 ), the amino sugar contained in the antitumour antibiotic elsamicin A, has been synthesized in eight steps (26% overall yield) from known building blocks derived from glycine, L-valine, and L-threonine. Direct and selective construction of the key intermediate 6 , with the complete backbone and the proper stereochemical configuration, is accomplished by a syn -aldol type reaction between lithiated Schollkopf's bislactime ether 5 and a 1,3-dioxolane-4-carboxaldehyde (−)- 3 .

1-Deoxygalactostatin ( 2 ) and (2 S , 3 S , 4 R , 5 S )-trihydroxypipecolic acid ( 15 ) have been synthesised from known building blocks derived from glycine, d -valine and l -tartaric acid (eight and seven steps, with 23% and 27% yield, respectively), via a syn -aldol reaction between 4- O-(tert -butyldiphenylsilyl)-2,3- O -isopropylidene- l -threose ( 6 ) and the stannous salt of the Schollkopf's bislactim ether 7b .

1-Deoxy-d-talonojirimycin ((-)-3) has been synthesised in four steps (38% yield), via a syn-aldol reaction between 2,3-O-isopropylidene-d-erythrose (5) and the stannous salt of the Schollkopf's bislactim ether 6 followed by the chemoselective oxidation and intramolecular reductive amination of 1,4-diol and lactol key intermediates, 8 and 9, respectively.