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The synthesis of three novel metallodendrimers, each composed of one central and six peripheral [[[Re.sub.6][([mu.sub.3]-Se).sub.8]].sup.2+] core-containing clusters linked by pyridyl-based bridging ligands is described. It is found that individual clusters behave independently of one another within the same dendritic structure when adequately long nonconjugated bridging ligands are utilized, whereas in the case of a conjugated linking group, the clusters are appreciably coupled.

A series of near-IR emitting organic light-emitting diodes were prepared using poly(vinyl-carbazole) (PVK) as the hole transport polymer, aluminum quinolate (Alq3) or sulfonamide derivates (Al(qs)3) as the host dye (H), and phthalocyanine (Pc) or naphthalocyanine (NPc) dopants as the guest dyes. It reveals that the hole captured by the guest dye from oxidized PVK, followed by cross reaction were an important charge trapping light producing pathway at sufficiently high concentrations of the guest dye.

Several past studies have demonstrated the effects of anthropogenic noise on populations of animals. Yet, differing effects of noise by age and subsequent changes in the age structure of populations are poorly understood. We experimentally tested the effects of traffic noise alone on the age structure of a community of migrating birds at a fall stopover site in south-western Idaho using an array of speakers - creating a phantom road - that replicated the sound of a roadway without other confounding aspects of roads. Both hatch-year and adult birds were negatively affected by noise - having lower capture rates, lower body condition and lower stopover efficiency along the phantom road when the noise was on compared to control conditions. However, hatch-year birds responded more strongly which lead to a significant shift in the ratio of hatch-year to adult birds under noisy conditions. Our previous work using the phantom road demonstrated that traffic noise can degrade the quality of a stopover site by affecting the ability of migrating birds to gain body condition. Here, we demonstrate differences between age classes such that although noise degrades habitat for both hatch-year and adult migrants, there are still differences in responses to noise between age groups. Despite alternative explanations of our results such as changes in behavior affecting capture likelihood, evidence suggests that younger birds avoided the phantom road more than adult birds perhaps because of different tradeoffs between foraging and predation risk and differing strategies of site selection during migration. [ABSTRACT FROM AUTHOR]

The reaction between the previously reported site-differentiated cluster solvate [Re6(μ3-Se)8-(PEt3)5(MeCN)](SbF6)2 (1) with pyridyl-based ditopic ligands 4,4′-trimethylenedipyridine (2), 1,2-bis(4-pyridyl)-ethane (3), and (E)-1,2-bis(4-pyridyl)ethene (4) afforded cluster complexes of the general formula [Re6(μ3-Se)8(PEt3)5(L)](SbF6)2 (5-7), where L represents one of the pyridyl-based ligands. Reacting these cluster complex-based ligands with the fully solvated cluster complex [Re6(μ3-Se)8(MeCN)6](SbF6)2 (8) produced dendritic arrays of the general formula {Re6(μ3-Se)8[Re6(μ3-Se)8(PEt3)5(L)]6}(SbF6)14 (9-11), each featuring six circumjacent [Re6(μ3-Se)8(PEt3)5]2+ units bridged to a [Re6(μ3-Se)8]2+ core cluster by the pyridyl-based ligands. Electrochemical studies using a thin-layer electrochemical cell revealed cluster-based redox events in these cluster arrays. For 9 (L = 2), one reversible oxidation event corresponding to the removal of 7 electrons was observed, indicating noninteraction or extremely weak interactions between the clusters. For 10 (L = 3), two poorly resolved oxidation waves were found. For 11 (L = 4), two reversible oxidation events, corresponding respectively to the removal of 1 and 6 electrons, were observed with the 1-electron oxidation event occurring at a potential 150 mV more positive than the 6-electron oxidation. These electrochemical studies suggest intercluster coupling in 11 via through-bond electronic delocalization, which is consistent with electronic spectroscopic studies of this same molecule. [ABSTRACT FROM AUTHOR]

Abstract: A tetracluster array {[Re6(μ 3-Se)8(PEt3)5]4[5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine]}(SbF6)8 (R4 ) featuring a central porphyrin core and four circumjacent [Re6(μ 3-Se)8]2+ units was synthesized by reacting the previously reported cluster solvate [Re6(μ 3-Se)8(PEt3)5(MeCN)](SbF6)2 (R) with 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine. Metallation of R4 with metal (Co2+, Ni2+, Cu2+, Zn2+) salts afforded the corresponding cluster-studded metalloporphyrins (R4 –Co, R4 –Ni, R4 –Cu, and R4 –Zn). All compounds were characterized by 1H and 31P NMR spectroscopy and elemental analysis (CHN). Electrochemical studies revealed one chemically reversible oxidation event attributable to the simultaneous removal of four electrons, one from each of the four cluster units. The uncoupled redox event suggests minimal electrical communication between the cluster sites. The cluster arrays were also studied by UV–vis spectroscopy. The electronic spectra of R4 –Co, R4 –Ni, and R4 –Cu each showed the absorptions of the metalloporphyrins and the cluster complex. For R4 –Zn, solvatochromism was observed. Its electronic absorptions in a variety of solvents of different dielectric constants were studied. To cite this article: B.K. Roland et al., C. R. Chimie 8 (2005) . [Copyright &y& Elsevier]

The cluster complex, “Re6(μ3-Se)8(PEt3)5(4-vinylpyridine)”(SbF6)2 (1), featuring the face-capped octahedral “Re6(μ3-Se)8”2+ cluster core and site-differentiating triethylphosphine and 4-vinylpyridine ligands has been synthesized and structurally characterized. The complex crystallized in monoclinic space group P21 with a=11.748(1)Å, b=15.1212(2)Å, c=19.941(2)Å, α=90°, β=94.411(3)°, γ=90°, V=3531.8(7)Å3, Z=2, R1=0.0531, wR2=0.0774. Copolymerization of styrene with 1 via the polymerizable 4-vinylpyridine ligand afforded a novel inorganic-organic hybrid composite of high molecular weight and a low polydispersity index. Structural integrity of the cluster building block is maintained upon hybrid formation. [ABSTRACT FROM AUTHOR]

The data in this paper are drawn from interviews with a stratified probability sample of 2996 Yoruba men and women aged 17 or above living in Lagos and Western States in June–July 1973. Although drawing upon other material from the 1 ½-hour interviews the discussion concentrates upon the family size ideals of these individuals. In addition to the customary measures of ideal family size, new measures of the limits of acceptable family size are described, together with the reactions of the whole sample to a wide range of statements relating to family size and the value of children. It is shown that the smallest family which would be acceptable to any appreciable proportion of the population is four children, which would be acceptable to 18% of all respondents. Comparative data from elsewhere in the developing world are presented to show that African family size ideals are amongst the highest in the world. Age, educational and occupational differentials in perceptions of different family sizes are also discussed. [ABSTRACT FROM PUBLISHER]

- The contribution of adrenal androgens to the maintenance and progression of so-called hormone-unresponsive prostatic carcinoma was studied in 20 patients with advanced relapsed disease. The role played by testicular androgens had been negated by prior orchiectomy or concurrent LHRH analogue therapy. Ketoconazole, an antifungal agent which inhibits adrenal and testicular androgenesis, administered in a dose of 400 mg 8-hourly, resulted in optimal suppression of adrenal androgens. The mean serum androstenedione concentration fell from 8.01 ± 0.84 nMol/l to 1.55 ± 0.25 nMol/l, P < 0.001, and serum testosterone from 1.25 ± 0.14 nMol/l to 0.36 ± 0.06 nMol/l, P <0.01, after 6 months treatment. There was, however, no significant difference between patients receiving 400 and those receiving 200 mg. Androgen suppression resulted in six objective and ten subjective clinical responses. Ablation of both testicular and adrenal androgens can now be achieved using ketoconazole in combination with orchiectomy or LHRH analogues, but the high incidence of side effects may preclude its use in all patients with prostatic cancer. The results of this study support the concept of 'total androgen ablation' as primary therapy in advanced prostatic cancer as a possible means of improving survival in this common malignancy. [ABSTRACT FROM AUTHOR]

A conventional assumption in the family planning literature is that birth control in developing countries is first adopted by high parity women who wish to cease childbearing. The empirical support for this belief has mainly been drawn from interview surveys on the motivations for, and the timing of, the inception of birth control among married women in areas where there is no cultural precedent for birth spacing by traditional means. This study, on the other hand, is based on data drawn from an area sample of 6,606 women, married or single, aged 15-59, in Ibadan, Nigeria, where there is a tradition for the practice of abstinence after a birth for the purpose of birth spacing. The Nigerian pattern revealed in the data presented here is indeed distinctive in many respects: (a) although premarital sex is prevalent, levels of premarital contraception are high; and (b) within marriage, spacing is the most prominent motivation for contraceptive practice, more important than the limitation of family size. [ABSTRACT FROM AUTHOR]

The data in this paper are drawn from interviews with a probability sample of 2652 once-married women under the age of 60 currently living with their husbands in 1971 in metropolitan Melbourne. Although drawing from other material from the 2½ hr interviews the discussion concentrates upon the family size ideals of these wives. In addition to the customary measures of ideal family size, new measures of the upper and lower limits of acceptable family size are described, together with the reactions of the whole sample to a wide range of specified family sizes and the reasons for accepting or rejecting them. It is shown that the eventual achievement of zero population growth will almost certainly depend upon the two-child family becoming the norm for the great majority of couples, since childless or one-child marriages are desired by only 2% of couples. Currently, however, 20% of wives consider two-child families to be undesirably small. The marked religious, country of origin and educational differentials in acceptance of the two-child family are also discussed. [ABSTRACT FROM PUBLISHER]

Describe an approach to a laparoscopic repair of a uterine isthmocele using hysteroscopic guidance. N/A The procedure was performed at a large tertiary care center that is also a teaching hospital. The patient was positioned in dorsal lithotomy in stirrups. Three 5mm ports were placed including an umbilical port and a right and left lower quadrant port placed 10mm from the midline above the level of the anterior superior iliac spine. Hysteroscopy was performed to identify the defect. The defect was then trans-illuminated and visualized on laparoscopy to aid in proper resection and repair. N/A The paravesical space was opened. A bladder flap was developed to expose the isthmocele in the lower uterine segment. The defect in the myometrium was excised circumferentially. The defect was then closed in three layers. The endometrium was closed with a running 3-0 monocryl suture. The myometrium and serosa were closed with a running unidirectional barbed suture in two layers. The peritoneum overlying the bladder was re-approximated with the unidirectional barbed suture as well. N/A Hysteroscopic guidance should be considered as an aid in the laparoscopic approach to repairing symptomatic uterine scar defects. [ABSTRACT FROM AUTHOR]

The most common urological manifestation of Henoch-Schönlein purpura is focal proliferative glomerulonephritis. Ureteric obstruction as a consequence of the disease has been reported in children but is rare. We report an adult male patient with Henoch-Schönlein purpura causing unilateral, bi-focal, recurrent ureteric obstruction. We speculate that ureteric involvement in Henoch-Schönlein purpura may be more common than hitherto suspected and that even with a demonstrable obstructive episode, consideration must be given for an initial conservative approach. [ABSTRACT FROM AUTHOR]

Examines the long term luteinizing hormone releasing hormone treatment for prostatic cancer in Great Britain. Failure of treatment; Implication in serum lutenizing hormone and testosterone; Improvement in daily administration.