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Abstract: A partial interaction based analysis to simulate the behaviour of RC beams with prestressed unbonded tendons is proposed. Unlike bonded reinforcement, the strain developed in unbonded reinforcing tendons under bending is uniform along the length of the member and is thus member dependant. Conventional analysis techniques incorporate correction factors and empirical components in defining the strain developed in both the unbonded and bonded reinforcement. Being semi-empirical, the post-cracking analysis cannot directly simulate the effects of tension-stiffening on the untensioned bonded reinforcement. Accordingly, this paper presents a segmental moment–rotation approach for simulating the behaviour of RC beams with unbonded prestressed reinforcement, such that the mechanics of the approach removes the reliance on empiricisms in defining the reinforcement and unbonded tendon behaviour. Validated against experimental results, the approach is shown to accommodate concrete creep, shrinkage and reinforcement relaxation, thus enabling prestressing losses to be quantified. [Copyright &y& Elsevier]

Abstract: Transition metal complexes [Co(cyclen)(NH3)2](ClO4)3⋅H2O (cyclen=1,4,7,10-tetraazacyclododecane) (2), [Co(NH3)5(OH2)](CF3SO3)3 (3) [Ni(NH3)6]Br2 (4) and [Ru(NH3)6]Cl3 (5) were tested against Sindbis infected baby hamster kidney (BHK) cells and show differential effects from the previously reported anti-viral complex [Co(NH3)6]Cl3 (1). The macrocyclic complex 2 and labile aqua complex 3 show either no or little effect on the survival on Sindbis virus-infected cells as compared to that for 1, which show a monotonic increase in % BHK cell survival. Nickel and ruthenium ammine complexes 4 and 5 had a moderate influence of cell survival. While the results showed some anti-viral activity for some of the structural variations, it appears that 1, with its potential to be a broad-spectrum anti-viral compound, occupies a unique position in its ability to both significantly enhance cell survival and to decrease viral expression of infected cells. We also show that 1 also shows anti-viral activity against Adenovirus lending support to the broad-spectrum potential of this complex. [Copyright &y& Elsevier]

Abstract: The water-soluble chelating phosphine ligand tris(2-carboxyethyl)phosphine (TCEP) reacts with cobalt(II) chloride in water to give the mixed-valence Co(III)/Co(II)/Co(III) complex [Co{P(CH2CH2COO)2(CH2CH2COOH)}2]2[Co(H2O)4][Na2(H2O)4]Cl2 ·6H2O (1). Structural analysis of 1 using single-crystal X-ray diffraction reveals a trimetallic sodium bridged structure in which TCEP adopts a tridentate chelating mode towards Co(III), and a bridging mode towards Co(II) and Na ions. [Copyright &y& Elsevier]

Objective: It is now accepted that corticosteroid administration before preterm delivery reduces neonatal mortality and morbidity. However, corticosteroid use in the setting of rupture of membranes remains controversial.Study Design: We reviewed data from the first and largest randomized trial in this area and included them in a new meta-analysis.Results: Data from 318 women with rupture of membranes in the Auckland Trial showed that there was a trend toward reduction of the risk of respiratory distress syndrome with corticosteroids but that this trend did not reach statistical significance. There was little effect on the risks of neonatal death, intraventricular hemorrhage, and fetal, neonatal, or maternal infection. Combined data from 15 controlled trials involving >1400 women with rupture of membranes confirmed that corticosteroids reduce the risks of respiratory distress syndrome (relative risk, 0.56; 95% confidence interval, 0.46-0.70), intraventricular hemorrhage (relative risk, 0.47; 95% confidence interval, 0.31-0.70), and necrotizing enterocolitis (relative risk, 0.21; 95% confidence interval, 0.05-0.82). They also may reduce the risk of neonatal death (relative risk, 0.68; 95% confidence interval, 0.43-1.07). They do not appear to increase the risk of infection in either mother (relative risk, 0.86; 95% confidence interval, 0.61-1.20) or baby (relative risk, 1.05; 95% confidence interval, 0.66-1.68). The duration of rupture of membranes does not alter these outcomes.Conclusion: The available data indicate that corticosteroid administration is beneficial in the setting of rupture of membranes. In our opinion further trials to address this question cannot be justified. [ABSTRACT FROM AUTHOR]

Current approaches to mapping submerged coral ecosystems by remote sensing techniques are largely confined to the identification of general reef features in shallow tropical waters. Technical difficulties in compensating for the attenuation of radiance through the water column, as well as an incomplete understanding about the specific spectral features of coral and other substrates under normal and stressed conditions, have limited mapping and assessment procedures. This paper reports on recent developments in mapping submerged coral assemblagesin Fiji using remotely sensed imagery and in situ field measurements. Preliminary results indicate that the spectral response of corals can be determined up to a depth of 10 m. An accurate and replicable procedure is proposed to quantify the spectral response of various corals and other submerged substrates to determine biodiversity and stress indicators for mapping and assessing coral ecosystems at site-specific and regional locations. Applications of the approach in establishing baseline information, assessing environmental change and managinglinked systems within an integrated coastal management framework arehighlighted. [ABSTRACT FROM AUTHOR]

The C. difficile Antimicrobial Resistance Surveillance (CDARS) study is a longitudinal investigation of both the molecular epidemiology and antimicrobial resistance phenotype of C. difficile isolated in Australia since 2013. Increasing rates of hospital and community-acquired C. difficile infections (CA-CDI) in children have been recorded in many parts of the world, however, research in Australia has been limited. [Extracted from the article]

“Ligand-free” citrate-stabilized 10 nm gold nanoparticles (AuNPs) promote the hydrolysis of the thiophosphate ester methyl parathion (MeP) on the surface of gold as a function of pH and two temperature values. At 50 °C, the active surface gold atoms show catalytic turnover ∼4 times after 8 h and little turnover of gold surface atoms at 25 °C with only 40% of the total atoms being active. From Michaelis–Menten analysis, k cat increases between pH 8 and 9 and decreases above pH 9. A global analysis of the spectral changes confirmed the stoichiometric reaction at 25 °C and the catalytic reaction at 50 °C and mass spectrometry confirmed the identity of p -nitrophenolate ( PNP ) product. Additional decomposition pathways involving oxidation and hydrolysis independent of the formation of PNP were also seen at 50 °C for both catalyzed and un-catalyzed reactions. This work represents the first kinetic analysis of ligand-free AuNP catalyzed hydrolysis of a thiophosphate ester. [ABSTRACT FROM AUTHOR]

Cobalt(III) and rhodium(III) complexes containing the water-soluble porphyrin ligand meso -tri(4-sulfonatophenyl)mono(4-carboxyphenyl)porphine (C 1 S 3 TPP), [Rh(C 1 S 3 TPP)]Na x •nH 2 O (1) and [Co(C 1 S 3 TPP)]Na x •nH 2 O (2) were prepared from the direct reaction of free porphyrin and metal chloride salts in refluxing MeOH/DMF or EtOH/H 2 O. Compounds 1 and 2 were characterized using UV–vis and 1H NMR spectroscopies, and high-resolution mass spectrometry. Cell culture based assays of opioid receptor activation showed that while the rhodium complex reduced fentanyl opioid activity 113-fold to an IC50 value of 1.7 μM, the cobalt complex reduced fentanyl activity by 160-fold to an IC50 value of 2.4 μM. An oxidative mechanism for fentanyl breakdown is proposed. [Display omitted] • Cobalt and rhodium porphyrin complexes remove fentanyl from aqueous solution. • Fentanyl breakdown products identified using high resolution mass spectrometry. • Catalytic mechanism involves tandem N -dealkylation oxidation. • Cell-based assays show reduction of opidoid activity in vitro. [ABSTRACT FROM AUTHOR]

Abstract: The compressive response of rigidly supported stainless steel sandwich panels subject to a planar impulsive load in water is investigated. Five core topologies that spanned a wide range of crush strengths and strain-dependencies were investigated. They included a (i) square-honeycomb, (ii) triangular honeycomb, (iii) multi-layer pyramidal truss, (iv) triangular corrugation and (v) diamond corrugation, all with a core relative density of approximately 5%. Quasi-statically, the honeycombs had the highest peak strength, but exhibited strong softening beyond the peak strength. The truss and corrugated cores had significantly lower strength, but a post yield plateau that extended to beyond a plastic strain of 60% similar to metal foams. Dynamically, the transmitted pressures scale with the quasi-static strength. The final transmitted momentum increased slowly with core strength (provided the cores were not fully crushed). It is shown that the essential aspects of the dynamic response, such as the transmitted momentum and the degree of core compression, are captured with surprising fidelity by modeling the cores as equivalent metal foams having plateau strengths represented by the quasi-static peak strength. The implication is that, despite considerable differences in core topology and dynamic deformation modes, a simple foam-like model replicates the dynamic response of rigidly supported sandwich panels subject to planar impulsive loads. It remains to ascertain whether such foam-like models capture more nuanced aspects of sandwich panel behavior when locally loaded in edge clamped configurations. [Copyright &y& Elsevier]

Abstract: We have investigated the potential antiviral activity of three cobalt(III) compounds. Two compounds, Co(III)–cyclen–methylbenzoic acid and its methyl ester derivative, are based on the macrocyclic chelator, cyclen, and were synthesized in our laboratory. Both compounds have been shown to bind tightly to nucleic acids and to hydrolyze phosphodiester bonds. However, neither compound exhibited any significant antiviral activity in an in vitro model of Sindbis virus replication. In contrast, a third compound, Co(III)hexammine, significantly inhibited Sindbis virus replication in baby hamster kidney (BHK) cells in a dose- and time-dependent manner. In plaque assays, the incubation of Co(III)hexammine with Sindbis virus resulted in a dose-dependent decrease in virus replication when measured at both 24 and 48-h post-infection. Over the concentration range of 0–5mM Co(III)hexammine, the IC50 for the inhibition of viral replication was determined to be 0.10±0.04mM at 48h. Additionally, when BHK cell monolayers were pretreated with Co(III)hexammine for 6h prior to Sindbis infection, optimal cellular morphology and plasma membrane integrity were observed at 0.6–1.2mM Co(III)hexammine. Analysis by flow cytometry confirmed that Co(III)hexammine mediated a concomitant dose-dependent increase in BHK cell viability and a decrease in the percentage of Sindbis virus-infected cells (IC50 =0.13±0.04mM). Our findings demonstrate for the first time that Co(III)hexammine possesses potent antiviral activity. We discuss our findings within the context of the ability to further functionalize Co(III)hexammine to render it a highly specific antiviral therapeutic reagent. [Copyright &y& Elsevier]

BACKGROUND: Type 2 diabetes mellitus (DM) is a progressive disease. Initial therapy begins with dietary and lifestyle modifications. However, as the disease progresses, glycemic control becomes more difficult to attain, often requiring > or =1 oral antihyperglycemic medication (OAM), and finally the addition of insulin to the OAMs and insulin monotherapy. OBJECTIVE: This study was designed to determine the effect of pioglitazone 30 mg plus insulin (PIO + INS) versus placebo plus insulin (PLB + INS) on glycemic control, the serum lipid profile, and selected cardiovascular risk factors in patients with type 2 DM whose disease was inadequately controlled with insulin therapy alone despite efforts to intensify such treatment. METHODS: This was a 6-month, randomized, double-blind, prospective, multicenter, placebo-controlled, parallel-group study. Patients with type 2 DM and a glycosylated hemoglobin (HbA(1c)) value > or =7.5% who were using insulin (with or without OAMs) entered a 3-month insulin intensification phase to achieve blood glucose targets with insulin monotherapy. After insulin intensification, those patients with HbA(1c) values > or =7.0% were randomized to PIO + INS or PLB + INS. The primary end point was the change in HbA(1c) from baseline. Cardiovascular risk markers (highly sensitive C-reactive protein [hs CRP] and plasminogen activator inhibitor-1 [PAI-1]) were measured at baseline and end point. RESULTS: Of the 289 patients randomized to treatment (mean [SD] age, 58.9 [7.1] years; 164 women, 125 men), 142 received PIO + INS and 147 received PLB + INS. A total of 263 patients completed the study. After 6 months, PIO + INS reduced mean HbA(1c) (-0.69%; P < 0.002) and mean fasting plasma glucose ([FPG] -1.45 mmol/L; P < 0.002) from baseline. PLB + INS produced no significant changes in HbA(1c) or FPG. The between-treatment differences for HbA(1c) (-0.55%; P < 0.002) and FPG (-1.80 mmol/L; P < 0.002) occurred despite a reduction of insulin dose in the PIO + INS group from baseline (-0.16 U/d . kg; P < 0.002). Significant between-group differences were observed for high-density lipoprotein cholesterol (0.13 mM; P < 0.002), triglycerides (ratio of geometric mean [PIO/PLB], 0.871; P < 0.01), atherogenic index of plasma (-0.11; P < 0.002), PAI-1 (-5.10 U/mL; P < 0.001), and hs CRP (-1.47 mg/L; P < 0.05). The rate of clinical and biochemical hypoglycemia (blood glucose <2.8 mmol/L) did not differ statistically between treatment groups, but reported incidences of subjective hypoglycemia occurred more often with PIO + INS than with PLB + INS (90 vs 75; P < 0.05). Edema was more common with PIO + INS than with PLB + INS (20 vs 5 instances, respectively), as was gain (mean [SEM]) in body weight (4.05 [4.03] vs 0.20 [2.92] kg, respectively). CONCLUSION: Adding pioglitazone to insulin in these study patients with type 2 DM whose disease was inadequately controlled with insulin monotherapy further improved their glycemic control. [ABSTRACT FROM AUTHOR]

The title compound, cis-[PtCl2(p-TPPTP(H)7)2]Cl2 · 4H2O · (CH3CH(OH)CH3) (TPPTP=triphenylphosphine triphosphonate), is formed via crystallization from a water-isopropanol solution of cis-[PtCl2(TPPTP(H6))2]. The coordination geometry around platinum is distorted square planar with two coordinated chloride ligands, and two free chloride ions in the crystal lattice. Two of the phosphonic acid groups are protonated –PO3H3 + and the complex contains extensive intra- and inter-molecular hydrogen bonding. [Copyright &y& Elsevier]

Previous reports indicate that patients who do not develop Q waves after thrombolytic therapy are a different population with a better long-term survival than those who do develop Q waves. However, the use of resources, quality of life, and health status of this population have not been fully evaluated. Using data from the Economics and Quality of Life subset of the Global Utilization of Streptokinase and tPA for Occluded Arteries study, we examined 30-day and 1-year mortality, use of resources, and quality-of-life measures among 1,830 of 3,000 patients with acute myocardial infarction and ST-segment elevation treated with thrombolytic therapy. At hospital discharge, 555 patients (30.2%) had not developed Q waves. These patients had lower mortality than patients with Q waves at 30 days (1.6% vs 4.5%, p <0.01) and at 1 year (4.7% vs 6.8%, p <0.04). Recurrent chest pain and dyspnea were similar at 30 days and 1 year. Patients without Q waves had significantly more angiography and trends toward higher readmission, revascularization, and use of calcium antagonists at 30 days. Angiography, revascularization, readmission, and quality of life were equivalent from 30 days to 1 year, with no sign of late instability. Logistic regression analysis showed an association between in-hospital revascularization and better survival and quality of life at 1 year. Conversely, there was no association between in-hospital use of calcium antagonists and outcome to explain the lower mortality in non-Q-wave patients. The absence of Q waves after thrombolytic therapy is a marker of success, implying better prognosis and equivalent quality of life, use of resources, and health status than for patients with Q-wave acute myocardial infarction and no sign of long-term unstable clinical course. [ABSTRACT FROM AUTHOR]