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Hypertension is a major risk factor for vascular diseases such as stroke, myocardial infarction, and renal microvascular disease. The mechanism by which vascular disease develops is complex, and growing evidence suggests that an increase in reactive oxygen species during hypertension is a major contributing factor. NADPH oxidase, the primary source of reactive oxygen species in the cardiovascular system, is a strong candidate for the development of therapeutic agents to ameliorate hypertension and end-organ damage.

In Chile the integration of Gracilaria chilensiswith salmon culture has shown high potential. Seaweed integrated aquaculture is of great interest as it allows waste recycling within fed cage aquaculture. The development of economically feasible suspended methods of seaweed cultivation is therefore of high importance. Hence, production and performance of two suspended Gracilariacultivation methods, spore inoculated ropes and ropes with twined field collected seaweed, were studied in open water. The production from spore-seeded ropes was comparable to that of twined ropes for the first month of culture. Thereafter, the twined ropes had a significantly higher productivity. Fish farm wastes had no significant fertilizing effect upon Gracilariagrowth rate. In addition, spore-originated thalli and field collected thalli were compared under laboratory conditions and in suspended culture using the same cultivation method. Spore-originated thalli had a 50% lower growth rate than the field collected thalli under laboratory conditions; however, no significant differences were detected in the field. Also, the occurrence of spore coalescence growth enhancement was not significant on the spore-seeded ropes. It was concluded that spore-originated cultivation techniques could be of interest for an integrated open seawater aquaculture system due to the high levels of Gracilariapolymorphism. This would result in greater adaptability to environmental variations, and a continuous supply of restocking material.

The syntheses of [1,3,5-{(η²-dppe)(η⁵-C5Me5)FeC&tbd1;C-4-C6H4C&tbd1;C}3C6H3] (1) and [(η²-dppe)(η⁵-C5Me5)Fe(C&tbd1;C-1,4-C6H4C&tbd1;CPh)] (2) are reported, together with an X-ray diffraction study of 2. The linear optical spectra of these compounds reveal characteristic low-energy transitions at 430 and 436 nm, respectively, significantly red shifted in comparison to those recorded for [1,3,5-{(η²-dppe)(η⁵-C5Me5)FeC&tbd1;C}3C6H3] (3) and [(η²-dppe)(η⁵-C5Me5)FeC&tbd1;CPh] (4), respectively. Cubic nonlinear optical response data for 1, 2, and 4 are reported. Cubic molecular nonlinearities by Z-scan at 695 nm reveal an increase in nonlinearities upon introduction of the ligated metal unit and progression from linear monometallic complex to octupolar trimetallic complex. Oxidation of 1 to 1³⁺ results in a change of sign and magnitude of the imaginary (absorptive) part of the third-order nonlinearity; that is, the molecule can be electrochemically cycled between two-photon absorber and saturable absorber states.

The “first-generation” alkynylruthenium dendrimers 1,3,5-C6H3(4-C&tbd1;CC6H4C&tbd1;C-trans-[Ru(dppe)2]C&tbd1;C-3,5-C6H3{4-C&tbd1;CC6H4C&tbd1;C-trans-[Ru(4-C&tbd1;CC6H4R)(dppe)2]}2)3 [R = H (19), NO2 (20)], containing nine dialkynylruthenium centers, have been prepared by convergent synthesis. Reaction of 3 equiv of 1-iodo-4-trimethylsilylethynylbenzene with triethynylbenzene, under Sonogashira coupling conditions, followed by deprotection with tetra-n-butylammonium fluoride affords 1,3,5-C6H3(4-C&tbd1;CC6H4C&tbd1;CH)3 (2), which is reacted with cis-[RuCl2(L)2] (L = dppe, dppm) to afford the octopolar, triruthenium dendritic cores 1,3,5-C6H3{4-C&tbd1;CC6H4C&tbd1;C-trans-[RuCl(L)2]}3 [L = dppe (5), L = dppm (6)] via the vinylidene intermediates [1,3,5-C6H3{4-C&tbd1;CC6H4CH&dbd;C-trans-[RuCl(L)2]}3](PF6)3 [L = dppe (3), L = dppm (4)]. Reaction of 5 with terminal alkynes 4-HC&tbd1;CC6H4R (R = H, NO2, NEt2) affords a series of related dialkynylruthenium zero-generation dendrimers 1,3,5-C6H3{4-C&tbd1;CC6H4C&tbd1;C-trans-[Ru(4-C&tbd1;CC6H4R)(dppe)2]}3 [R = H (7), NO2 (8), NEt2 (9)]. Reaction of 3 equiv of trans-[Ru(4-C&tbd1;CC6H4C&tbd1;CH)(C&tbd1;CPh)(dppe)2] with 1,3,5-triiodobenzene under Sonogashira coupling conditions also affords 7, together with the homo-coupled trans,trans-[(dppe)2(PhC&tbd1;C)Ru(4,4‘-C&tbd1;CC6H4C&tbd1;CC&tbd1;CC6H4C&tbd1;C)Ru(C&tbd1;CPh)(dppe)2]. The first-generation dendrimers 19 and 20 are prepared by coupling core 5 with the dendrons 1-(HC&tbd1;C)C6H3-3,5-{4-C&tbd1;CC6H4C&tbd1;C-trans-[Ru(4-C&tbd1;CC6H4R)(dppe)2]}2 [R = H (17), NO2 (18)]. Thus, reaction of 1-(Me3SiC&tbd1;C)C6H3-3,5-(4-C&tbd1;CC6H4C&tbd1;CH)2 (12), obtained from 1-iodo-3,5-dibromobenzene through a series of Sonogashira coupling and transhalogenation reactions, with cis-[RuCl2(dppe)2] affords 1-(Me3SiC&tbd1;C)C6H3-3,5-{4-C&tbd1;CC6H4C&tbd1;C-trans-[RuCl(dppe)2]}2 (13), which can be reacted with appropriately functionalized terminal alkynes to afford the series 1-(Me3SiC&tbd1;C)C6H3-3,5-{4-C&tbd1;CC6H4C&tbd1;C-trans-[Ru(4-C&tbd1;CC6H4R)(dppe)2]}2 [R = H (14), NO2 (15), NEt2 (16)]. Desilylation of 16 proceeds with decomposition; in contrast, treatment of 14 and 15 with tetra-n-butylammonium fluoride gives 17 and 18, which are coupled with 5 under basic conditions to afford the dendritic complexes 19 and 20 via in situ deprotonation of the vinylidene complex intermediates. A transmission electron micrograph of 19 supported on alumina reveals molecules that are approximately 6 nm in diameter, in agreement with molecular modeling studies.

The pseudooctahedral monocluster compounds M2Ir2(μ4-η²-R¹C2R²)(μ-CO)4(CO)4(η⁵-C5H4Me)2 (M = Mo, R² = Ph, R¹ = H (12), Ph (13), Me (14); M = W, R² = Ph, R¹ = Me (15); M = Mo, R¹ = n-hexyl, R² = C6H4-4-CHO (16), C6H4-4-CH2P(O)(OEt)2 (17)) have been prepared from reactions between the tetrahedral cluster compounds M2Ir2(CO)10(η⁵-C5H4Me)2 and the alkynes R¹C2R². Similar reactions between tetrahedral cluster precursors and di- or triynes have afforded the related compounds [M2Ir2(μ-CO)4(CO)4(η⁵-C5H4R)2]2(μ8-η⁴-R¹C2BC2R¹) (R = H, R¹ = H, B = 4-C6H4-(E)-CH&dbd;CH-4-C6H4, M = Mo (18); R = Me, R¹ = n-hexyl, B = 4-C6H4, M = Mo (19), W (20); R = Me, R¹ = n-hexyl, B = 4-C6H4-(E)-CH&dbd;CH-4-C6H4, M = Mo (22), W (23); R = Me, R¹ = n-hexyl, B = 4-C6H4-(E)-CH&dbd;CH-4-C6H4-(E)-CH&dbd;CH-4-C6H4, M = Mo (24); R = Me, R¹ = H, B = (CH2)2, M = W (27)), [Mo2Ir2(μ-CO)4(CO)4(η⁵-C5H4Me)2]3{μ12-η⁶-1,3,5-C6H3[(E)-CH&dbd;CHC6H4-4‘-C2(CH2)5Me]3} (25), and W2Ir2(μ4-η²-R¹C2R²)(μ-CO)4(CO)4(η⁵-C5H4Me)2 (R¹ = n-hexyl, R² = 4-C6H4C&tbd1;C(CH2)5Me (21); R¹ = H, R² = (CH2)2C&tbd1;CH (26)). Compounds 18−20 and 22−25 contain two or three cluster units linked by unsaturated bridges, while 27 contains two cluster units linked by a saturated bridge. Compound 22 was prepared in lower yield by coupling 16 and 17 under Emmons−Horner conditions. Structural studies of examples of mono- (15), di- (22), and tricluster (25) compounds have been undertaken. Cyclic voltammetric scans for 12−15, 19, 20, 22−24, 27 and the related cluster W2Ir2(μ4-η²-PhC2Ph)(μ-CO)4(CO)4(η⁵-C5H4Me)2 (4) have been collected. All compounds show a reversible/partially reversible oxidation, followed by an irreversible oxidation process; potentials for the former increase on replacement of tungsten by molybdenum and alkyne substituent variation Me < H < Ph. UV−vis−near-IR spectroelectrochemical studies of the first oxidation process for 12, 15, and 20 show similar spectral progressions for these mono- and dicluster compounds. The reductive cyclic voltammetric scans for 4, 12−15, 22−24, and 27 all show one irreversible reduction process; compounds 19 and 20, distinguished by possessing the shortest unsaturated bridge, show two reduction processes.

A series of new acetylide complexes of the type [Fe(η⁵-C5H5)(P&arcraise;P)(p-C&tbd1;CC6H4R)] (P&arcraise;P = DPPE (=1,2-bis(diphenylphosphino)ethane), (R)-PROPHOS (=(R)-(+)-1,2-bis(diphenylphosphino)propane), R = NO2, C6H4NO2, (Z)-C(H)&dbd;C(H)C6H4NO2, (E)-C(H)&dbd;C(H)C6H4NO2) have been synthesized by halide abstraction from the precursors [Fe(η⁵-C5H5)(P&arcraise;P)(I)] and fully characterized. Quadratic hyperpolarizabilities (β) for the complexes have been determined by hyper-Rayleigh scattering at 1064 nm. The influence on the nonlinear response of acetylide chain length in proceeding from 4-nitrophenylethynyl to 4-nitrobiphenylethynyl and 4-nitro-(E)-stibenylethynyl has been studied, revealing values of the first hyperpolarizabilities among the highest reported for organometallic molecular materials. Comparisons on the nonlinear efficiencies are drawn with the related well-known families of compounds [Ru(η⁵-C5H5)(PR3)2(p-C&tbd1;C−(aryl)−NO2)] and [Fe(η⁵-C5H5)(P&arcraise;P)(p-N&tbd1;C−(aryl)−NO2)]⁺. Cubic hyperpolarizabilities (γ) determined by Z-scan at 800 nm are consistent with an increase in γ upon replacing Ru by the more easily oxidizable Fe and upon chain-lengthening the delocalizable π-bridging unit (proceeding from 4-C6H4 to (E)-4,4‘-C6H4CH&dbd;CHC6H4). X-ray crystallographic structures of complexes [Fe(η⁵-C5H5)(DPPE)(p-C&tbd1;CC6H4NO2)] and [Fe(η⁵-C5H5)(DPPE)((E)-p-C&tbd1;CC6H4C(H)&dbd;C(H)C6H4NO2)] were studied in order to investigate the existence of π-back-donation suggested by spectroscopic and electrochemical data. Crystal packing was analyzed with the aim of assessing the alignment of the molecules in the lattice and hence suggesting the magnitude of NLO properties at the macroscopic level.

The syntheses of trans-[Ru(C&dbd;CHR)Cl(pp)2]PF6 (pp = dppm, R = 4-C6H4C&tbd1;CPh, 4-C6H4CHO, 4,4‘-C6H4C&tbd1;CC6H4NO2, (E)-4,4‘-C6H4CH&dbd;CHC6H4NO2, 4,4‘,4‘ ‘-C&tbd1;CC6H4C&tbd1;CC6H4C&tbd1;CC6H4NO2; pp = dppe, R = 4-C6H4CHO, (E)-4,4‘-C6H4CH&dbd;CHC6H4NO2) and trans-[Ru(C&tbd1;CR)Cl(pp)2] (pp = dppm, R = 4-C6H4C&tbd1;CPh, 4-C6H4CHO, 4,4‘-C6H4C&tbd1;CC6H4NO2, (E)-4,4‘-C6H4CH&dbd;CHC6H4NO2, 4,4‘,4‘ ‘-C&tbd1;CC6H4C&tbd1;CC6H4C&tbd1;CC6H4NO2; pp = dppe, R = 4-C6H4CHO, (E)-4,4‘-C6H4CH&dbd;CHC6H4NO2) are reported, together with X-ray structural studies of trans-[Ru(C&tbd1;CR)Cl(pp)2] (pp = dppm, R = 4-C6H4C&tbd1;CPh; pp = dppe, R = 4-C6H4CHO, (E)-4,4‘-C6H4CH&dbd;CHC6H4NO2). Cyclic voltammetric, linear optical, and quadratic and cubic nonlinear optical response data for these new complexes, together with the corresponding data for the previously reported trans-[Ru(C&dbd;CHR)Cl(pp)2]PF6 (pp = dppm, R = Ph, 4-C6H4NO2; pp = dppe, R = Ph, 4-C6H4NO2) and trans-[Ru(C&tbd1;CR)Cl(pp)2] (pp = dppm, R = Ph, 4-C6H4NO2, (E)-4,4‘-C6H4CH&dbd;CHC6H4NO2; pp = dppe, R = Ph, 4-C6H4NO2), are reported. Oxidation potentials for the Ru^II/III couple increase on proceeding from the neutral alkynyl complex to the analogous cationic vinylidene complex and on introduction of an acceptor group (CHO or NO2); the complexes with 4-C&tbd1;CC6H4NO2 ligands are the most difficult to oxidize. In some instances, the Ru^III/IV and Ru^I/II processes have been identified together with, where relevant, nitro-centered reduction processes. The oxidized and reduced vinylidene complexes are shown to transform electrochemically into the corresponding alkynyl complexes. Optical absorption maxima undergo a red shift upon increase of acceptor strength, replacement of the coligand dppm with dppe, and replacement of the alkynyl ligand yne linkage with an ene linkage. Proceeding from the vinylidene complex to an analogous alkynyl complex results in a small red shift in absorption maximum and a significant increase in extinction coefficient. Quadratic molecular nonlinearities by hyper-Rayleigh scattering measurements at 1064 nm increase upon introduction of ligated metal (proceeding from precursor alkyne to alkynyl or vinylidene complex), an increase in acceptor strength (introduction of CHO or NO2), alkynyl chain lengthening (in the series [4-C&tbd1;CC6H4]n-4-NO2, proceeding from n = 1 and 2 to 3), and replacing the yne linkage with an ene linkage. Significant differences in β value for two vinylidene/alkynyl complex pairs suggest that they could function as precursors to protically switchable quadratic NLO materials at 1064 nm. Cubic molecular nonlinearities by Z-scan measurements at 800 nm are in many cases characterized by negative real and significant imaginary components, indicative of two-photon effects; nevertheless, a substantial increase in |γ| on proceeding to the largest molecule, trans-Ru(4,4‘,4"-C&tbd1;CC6H4C&tbd1;CC6H4C&tbd1;CC6H4NO2)Cl(dppm)2, is observed. An order of magnitude difference in γimag values (and therefore two-photon absorption (TPA) cross sections σ2) for vinylidene/alkynyl complex pairs suggest that they have potential as protically switchable TPA materials at 800 nm.

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The reactions of Q[Au(acac)2] (Q = N(PPh3)2 (PPN; a), NPr4 (b); acac = acetylacetonato) with terminal alkynes of the type HC&tbd1;CC6H4R-4 in a 1:2 molar ratio affords the complexes Q[Au(C&tbd1;CC6H4R-4)2] (R = NO2 (1), C6H4NO2-4 (2), (E)-CH&dbd;CHC6H4NO2-4 (3)). The same alkynes react with [AuCl(CNBu^t)] in NEt3 to give the complexes [Au(C&tbd1;CC6H4R-4)(CNBu^t)] (R = NO2 (4), C6H4NO2-4 (5), (E)-CH&dbd;CHC6H4NO2-4 (6)). When NHEt2 is used instead of NEt3, attack of the secondary amine at the isonitrile ligand takes place and alkynyl carbene complexes of the type [Au(C&tbd1;CC6H4R-4){C(NHBu^t)(NEt2)}] (R = NO2 (7), C6H4NO2-4 (8), (E)-CH&dbd;CHC6H4NO2-4 (9)) are obtained. The crystal structures of 1a, 4, 7, and 9 have been determined. The cubic hyperpolarizabilities of 1a,b, 4−6, 8, 9, and the related complexes [Au(C&tbd1;CC6H4R-4)(PPh3)] (R = H (10), NO2 (11), 4-C6H4NO2 (12), (E)-CH&dbd;CHC6H4NO2-4 (13), C&tbd1;CC6H4NO2-4 (14), (Z)-CH&dbd;CHC6H4NO2-4 (15), (E)-N&dbd;CHC6H4NO2-4 (16)) have been determined by Z-scans at 800 nm. An increase in γreal is observed on replacing the coligand Bu^tNC by PPh3 (proceeding from 5 to 12 and from 6 to 13), introduction of the NO2 group (proceeding from 10 to 11), extending the arylalkynyl π-bridge (proceeding from 11 to 12−15), and replacing (Z)-CH&dbd;CH by the (E)-CH&dbd;CH linking unit (proceeding from 15 to 13).

We studied the early response to ovalbumin challenge in sensitized Brown-Norway rats through its effect on N2, He, and SF6phase III slopes of the single-breath washout and on indexes of lung function. Sensitized rats showed varying degrees of response in terms of pulmonary pressure (Pl), with increases ranging between 125 and 225% of baseline. The sensitized rats presented decreased quasistatic compliance, forced vital capacity, and end-expiratory flow, with all three lung function indexes showing a significant negative correlation with corresponding Plvalues. They also showed significant positive correlations of Plwith the N2, He, and SF6phase III slopes, reflecting diffusion-convection-dependent inhomogeneities generated by conformation changes throughout the entire rat lung. In addition, the rats showing the most marked Plincreases (>150% baseline Pl) also revealed a reversal of the SF6-He slope difference because of a more marked SF6than He slope increase. This latter finding suggests that the degree of structural heterogeneity during early response is even more marked in the most peripheral rat lung generations.

The objective of this study is to investigate if endothelin-1 (ET-1) gene expression changes during the early response phase following antigen challenge. We used sensitized Brown–Norway rats known to develop an early airway response after antigen challenge. After ovalbumin challenge, sensitized rats presented an early response, characterized by an increase in pulmonary pressure (209±14.53%,P<0.01) and diminished functional parameters (inspiratory capacity, forced vital capacity (FVC) and expiratory flow at 75% of FVC), compared to their respective basal values. ET-1 mRNA expression was assessed by reverse transcription and polymerase chain reaction using specific primers for prepro-ET-1. A group of unsensitized rats was used as control. ET-1 expression was significantly enhanced in sensitized rats during the early response (290±62%,P<0.01) compared to the control group. In conclusion, antigen challenge induces an activation of ET-1 gene expression during the early response in Brown–Norway rats, suggesting a contribution of this protein to the development of bronchoconstriction.

The purpose of this article is to discuss how the old and rather technocratic idea of expressing the state of affairs in a society in numbers, by means of social indicatros, can be given a more radical content. One idea is to measure not only how good a society is to its own citizens, but also how good or bad it is to the rest of the world. A second idea is to avoid abstractions like GNP and averages and try to develop measures that reflect the state of affairs at the level of human beings. A third idea is to find ways of developing indicators that would give less power to experts and more to people themselves. The article starts by giving the outline of a basic discussion on indicators, proceeds with a discussion of the basic values guiding the selection of indicators and ends with a presentation of the indicators.