Submerged and unsubmerged natural hydraulic jumps in a bedrock step-pool mountain channel (Fig. 1 Classical hydraulic jump with partially developed inflow conditions)

Fig. 1. Classical hydraulic jump with partially developed inflow conditions. F1 = 13.6, V1 = 4.7 m/s, B = 0.25 m, h = 0.020 mm, d1 = 0.012 mm, Q = 14 L/s. Photo courtesy of Dr. Hubert Chanson. published in: Geomorphology Volume 82, Issues 1-2, 6 December 2006, Pages 146-159 The Hydrology and Geomorphology of Bedrock Rivers doi:10.1016/j.geomorph.2005.09.024 Submerged and unsubmerged natural hydraulic jumps in a bedrock step-pool mountain channel Brett L. Vallé and Gregory B. Pasternacka

High- and low-volume resistance training similarly enhances functional performance in older adults

It is well known that resistance training improves muscle strength in older adults and may enhance or preserve functional performance. However, it is unclear if the volume of work undertaken in the elderly alters the response in functional performance. PURPOSE: To investigate the effect of a high- versus low-volume resistance training program on functional performance in older adults. METHODS: Thirty-two healthy men and women aged 65-78 years were randomly assigned to either a single-set (SS, n = 16) or 3-set (MS, n = 16) progressive resistance training program for 20 weeks. Groups trained 2 days per week using machine weights at 8 repetitions maximum (8-RM) for 7 upper and lower body exercises. Muscle strength was assessed by the 1-RM and functional performance by a battery of tests (repeated chair rise, usual and fast 6-m walk, 6-m backwards walk, floor rise to standing, stair climb, and 400-m walk time). RESULTS: Twenty-eight subjects completed the study. There was no difference between groups at baseline in muscle strength or functional performance. Whole body muscle strength significantly increased in both groups with greater gains in the 3-set group (MS 32.9 ± 3.1%; SS 18.6 ± 2.7%, mean ± SE; P < 0.01). Significant improvement (time effect, P < 0.01) occurred for both groups in the chair rise (MS 13.6 ± 3.2%; SS 10.2 ± 3.0%), 6-m backwards walk (MS 14.9 ± 3.3%; SS 14.3 ± 4.2%), stair climb (MS 6.4 ± 2.8%; SS 7.7 ± 3.1%) and 400-m walk (MS 7.4 ± 1.4%; SS 3.9 ± 1.2%). There were no interaction (group × time) effects for functional performance and no differences by sex. CONCLUSION: Resistance training that utilizes either a singleset or 3-set regimen may significantly and similarly improve functional performance in community-dwelling older adults. Enhancement of functional performance may prolong independence and improve quality of life. ©2004The American College of Sports Medicine

Ni-II and Zn-II complexes of the hexadentate macrocyclic ligand cis-6,13-dimethyl-1,4,8,11-tetraazacyclotetra- decane-6,13-diamine

The title pendent-arm macrocyclic hexaamine ligand binds stereospecifically in a hexadentate manner, and we report here its isomorphous Ni-II and Zn-II complexes (both as perchlorate salts), namely (cis-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine-kappa(6)N)nickel(II) diperchlorate, [Ni(C12H30N6)](ClO4)(2), and (cis-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine-kappa(6)N)zinc(II) diperchlorate, [Zn(C-12 H30N6)](ClO4)(2). Distortion of the N-M-N valence angles from their ideal octahedral values becomes more pronounced with increasing metal-ion size and the present results are compared with other structures of this ligand.

Nitrogen- and carbon-based isomerism in the copper(II) complexes of 6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine

A number of N- and C-based diastereomeric copper(II) complexes of the pendant-arm macrocyclic hexaamines trans- and cis-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine (L-1 and L-2) have been isolated and characterised. The crystal structures of the complexes RRSS-[CuL1(OH2)(2)][ClO4](2), SSRR-[Cu(H2L1)(OClO3)(2)]-[ClO4](2) . 2H(2)O RSRS-[CuL1(OClO3)]ClO4, RSRS-[CuL2(OClO3)]ClO4 and RRSS-[Cu(H2L2)(OClO3)(2)][ClO4](2) have been determined. Some unusual structural and spectroscopic variations are found across this series of diastereomers. The protonation constants of the pendant primary amines are dependent on the relative dispositions of the adjacent macrocyclic secondary amine H atoms, which is indicative of intramolecular hydrogen-bonding interactions.

Isomers of 1,4,8,11-tetraazacyclotetradecane-6,13-dicarboxylate characterized as cobalt(III) complexes

The major trans (1) and minor cis (2) isomers of 1,4,8,11-tetraazacyclotetradecane-6,13-dicarboxylate have been characterized as the complexes [Co(1)](ClO4) and [Co(H-2)(OH2)]Cl(ClO4).H2O. The former crystallized in the C-2/c space group and the latter in the P2(1)/c space group, with cell parameters a 16.258(7), b 9.050(3), c 15.413(6) Angstrom, beta133.29(3)degrees, and a 9.694(4), b 16.135(1), c 12.973(5) Angstrom, beta 93.00(2)degrees, respectively. Their characterization completes identification of the respective trans and cis isomers for the series of C-pendant macrocycles also including 1,4,8,11-tetraazacyclotetradecane-6-amine-13-carboxylate ((3), (4)) and 1,4,8,11-tetraazacyclotetradecane-6,13-diamine ((5), (6)). The complexes show limited distortion from octahedral geometry with the strain in the presence of the coordinated C-pendant carboxylate significantly reduced compared with that for the C-pendant amine in analogues, a consequence mainly of six-membered as opposed to five-membered chelate rings involving the pendant donor. A comparison of the physical properties for the trans isomers of the octahedral complexes of (1), (3), and (5), which reflect progressively increasing strain, is presented.