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Maximum Point (maximum + point)
Selected AbstractsEfficient Increase of DNA Cleavage Activity of a Diiron(III) Complex by a Conjugating Acridine GroupEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 34 2007Xiao-Qiang Chen Abstract A new diferric complex, Fe2Lb, in which a DNA intercalator (acridine) is linked to a precursor diferric complex (Fe2La), has been designed and synthesised as a hydrolytic cleaving agent of DNA. Compared with Fe2La (without the DNA intercalator) (La: 2,6-bis{[(2-hydroxybenzyl)(pyridin-2-yl)methylamino]methyl}-4-methylphenol), Fe2Lb [Lb: 5-(acridin-9-yl)- N -(3,5-bis{[(2-hydroxybenzyl)(pyridin-2-yl)methylamino]methyl}-4-hydroxybenzyl)pentanamide] leads to a 14-fold increase in the cleavage efficiency of plasmid DNA due to the binding interaction between DNA and the acridine moiety. The interaction has been demonstrated by UV/Vis absorption, CD spectroscopy, viscidity experiments and thermal denaturation studies. The hydrolytic mechanism is supported by evidence from T4 DNA ligase assay, reactive oxygen species (ROS) quenching and BNPP [bis(4-nitrophenyl) phosphate, a DNA model] cleavage experiments. The pH dependence of the BNPP cleavage by Fe2La in aqueous buffer media shows a bell-shaped pH,kobs profile with an optimum point around a pH of 7.0 which is in good agreement with the maximum point of the pH-dependent relative concentration curve of active species from the pH titration experiments. The determination of the initial rates at a pH of 7.36 as a function of substrate concentration reveals saturation kinetics with Michaelis,Menten-like behaviour and Fe2La shows a rate acceleration increase of 4.7,×,106 times in the hydrolysis of BNPP. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Debt, democratization, and development in Latin America: How policy can affect global warmingJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 1 2008René W. Aubourg The environmental Kuznets curve (EKC) hypothesis conjectures a nonlinear relationship between pollution and economic growth, such that pollution per capita initially increases as countries economically develop, but then reaches a maximum point before ultimately declining. Much of the EKC literature has focused on testing this basic hypothesis and, in studies that find evidence of an EKC, estimating the "turning point" level of development at which the per capita pollution-growth relationship changes sign. This approach has not emphasized the policy relevance of specification issues or the potential role of policy variables. This research explores a modified EKC specification which conditions the pollution-growth relationship on a country's level of debt and degree of democratization. These variables turn out to be significant, implying that different political and economic contexts can shift EKCs and their turning points. These findings suggest that policies to relieve debt burdens and institute political reform, in addition to their usual justifications, also could be used as a strategy to reduce carbon emissions from developing countries. © 2008 by the Association for Public Policy Analysis and Management. [source] A Short Note on Steady State Behaviour of a Petlyuk Distillation Column by Using a Non-Equilibrium Stage ModelTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2006Erika Fabiola Abad-Zarate Abstract A Petlyuk distillation column, considering equilibrium and non-equilibrium stage models, was studied. Rigorous simulations were conducted using Aspen PlusÔ RATEFRAC Module for the separation of ternary mixtures. According to the equilibrium model, the energy-efficient design of the Petlyuk column requires that the intermediate component be extracted from the maximum point in the composition profile in the main column. It was found that, for the intermediate component, mass transfer occurs from the vapour to the liquid phase from the top of the column to the stage where the side stream is extracted, from this point mass transfer occurs in the opposite direction. This point, considering the non-equilibrium model, corresponds to the stage in which the net mass transfer rate is zero. For the case of two segments per stage, it was found that the heat duties predicted by the equilibrium model are significantly lower than those obtained by using the non-equilibrium model, which is consistent with previous reported results. However, it is important to say that despite the higher energy duty predicted by the non-equilibrium model; both models predict significant energy savings. On a étudié une colonne de distillation de Petlyuk en considérant des modèles d'étage en équilibre et hors équilibre. Des simulations rigoureuses ont été menées au moyen du module RATEFRAC d'Aspen PlusÔ pour la séparation de mélanges ternaires. Selon le modèle en équilibre, une conception énergétiquement efficace de la colonne Petlyuk nécessite que le composant intermédiaire soit extrait du point maximum du profil de composition dans la colonne principale. On a trouvé que, pour le composant intermédiaire, le transfert de masse se produisait de la vapeur vers le liquide de la tête de la colonne jusqu'à l'étage où le courant secondaire est extrait; à partir de ce point le transfert de masse se produit dans la direction opposée. Ce point, en considérant le modèle hors équilibre, correspond à l'étage où le taux de transfert de masse net est nul. Dans le cas où il y a deux segments par étage, on a trouvé que les rendements thermiques prédits par le modèle en équilibre étaient significativement plus faibles que ceux obtenus à l'aide du modèle hors équilibre, ce qui est cohérent avec les résultats existants. Cependant, il est important de préciser que malgré le rendement énergétique plus élevé prédit par le modèle hors équilibre, les deux modèles fournissent des économies d'énergie significatives. [source] Likelihood and bayesian approaches to inference for the stationary point of a quadratic response surfaceTHE CANADIAN JOURNAL OF STATISTICS, Issue 2 2008Valeria Sambucini Abstract In response surface analysis, a second order polynomial model is often used for inference on the stationary point of the response function. The standard confidence regions for the stationary point are due to Box & Hunter (1954). The authors propose an alternative parametrization, in which the stationary point is the parameter of interest; likelihood techniques and Bayesian analysis are then easier to perform. The authors also suggest an approximate method to get highest posterior density regions for the maximum point (not simply for the stationary point). Furthermore, they study the coverage probabilities of these Bayesian regions through simulations. Approches vraisemblantiste et bayésienne pour I'inference portant sur le point stationnaire d'une surface de réponse quadratique Résumé: Dans l'analyse des surfaces de réponse, un polyn,me du second degré est souvent utilisé pour l'inférence portant sur le point stationnaire de la fonction de réponse. Les régions de confiance standards pour le point stationnaire sont dues à Box & Hunter (1954). Les auteurs proposent une paramétrisation différente dans laquelle le point stationnaire est le paramètre d'intér,t; ceci facilite l'emploi des techniques de vraisemblance et l'analyse bayésienne. Les auteurs suggèrent aussi une façon d'approximer les régions de plus haute densité a posteriori pour le point maximum (et non seulement pour le point stationnaire). De plus, ils étudient les propriétés de couverture des régions bayésiennespar voie de simulation. [source] Interventions for treating the posterior interosseus nerve syndrome: a systematic review of observational studiesJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 2 2006Bionka M. A. Huisstede Abstract For the posterior interosseus nerve syndrome (PINS), no randomised controlled trials or controlled clinical trials about the effectiveness of interventions are available; only case series can be found. Although the validity of case series is inferior to controlled trials, they may provide valuable data about the efficacy of treatment options. Therefore, we systematically reviewed all available observational studies on treatment of PINS. A literature search and additional reference checking was done. On the basis of previous checklists, we constructed a quality assessment and rating system to analyse the included case series. Studies with less than 50% of the maximum points on the methodological quality assessment were excluded from the analysis. The results are summarised according to a rating system for the strength of the scientific evidence. Six eligible case series for this review were found. After the data extraction and methodological quality assessment, two higher quality studies that evaluated the effectiveness of surgical decompression of the PIN were included in the final analysis. There is a tendency for the effectiveness of surgical decompression of the PIN in patients with PINS. The effectiveness of a conservative treatment for PINS is unknown because no higher quality studies are available. Additional high-quality controlled studies are needed to assess the level of ,conclusive evidence' for surgical treatment. There is also a need for high-quality controlled trials into the effectiveness of conservative treatments for PINS. [source] Latest news and product developmentsPRESCRIBER, Issue 17 2007Article first published online: 6 NOV 200 Drug information stilllacking for mentally ill Half of people with mental illness still have no say in the medication they are prescribed and one-third are not informed about side-effects, according to the latest report by the Healthcare Commission and the Commission for Social Care Inspection (www.health-carecommission.org.uk). The annual national review of adult mental health services found overall improvement among local intervention teams in 2005/06 compared with the preceding year, though all could improve further and the performance of 46 per cent were rated as only fair or weak. A survey of 7446 people with schizophrenia also showed that only 46 per cent had access to psychological treatments. More incentives for shift of care in Scotland Scotland has made good progress on shifting NHS care into the community but joined-up thinking, better information and incentives are needed to overcome barriers to better management of long-term conditions in adults, says Audit Scotland (www.audit-scotland.gov.uk). Reviewing progress on the 2005 strategy document Delivering for Health, Audit Scotland found good progress on asthma and diabetes services , partly due to the effects of the GMS contract. Better information about clinical activity, costs and effectiveness is needed to help redesign services. Patients with more than one long-term condition do not receive co-ordinated care and many want greater involvement in their care, the report concluded. Acorn, QOF and Guy Rotherham awards Entries are invited for the 2007 annual Acorn, QOF and Guy Rotherham Awards. The awards are run in association with the NHS Alliance, Improvement Foundation, British Cardiac Society, British Cardiac Patients Society and Prescriber. The CHD QOF Award, sponsored by Schering-Plough, recognises the achievement of an individual practice that gains maximum points in the CHD and heart failure QOF domains, and a second award is given to the primary care organisation (PCO) that achieves the best average scores across its practices. The entry form can be found at www.escriber.com. The closing date is 12 October. Entries are also invited for the Guy Rotherham Award from PCOs that can demonstrate they have delivered a high-impact change resulting in better outcomes and services for patients. For online entry go to www.improvementfoundation.org/guy rotherhamaward. Closing date is 5 October. Award winners will receive free entry for three to the NHS Alliance conference and the conference dinner. The winner of the Guy Rotherham Award will also receive £3000. NICE scores five out of six NICE acted unreasonably in relying solely on the Mini-Mental State Examination (MMSE) to define severity of Alzheimer's disease in its updated technology appraisals, with the effect of discriminating against people with learning or language difficulties, the High Court has ruled. The five other claims by Eisai that NICE acted unreasonably and irrationally were not upheld. This was the first court action against NICE in its eight-year history. It has now promised to publish revised appraisals on its website on 7 September and is consulting with Eisai, Shire Pharmaceuticals and the Alzheimer's Society on the best approach. PPRS reform follows Office of Fair Trading report The Government is to renegotiate the Pharmaceutical Price Regulation Scheme (PPRS) following the critical report by the Office of Fair Trading (OFT). In February, the OFT recommended renegotiation of the PPRS to reward innovation and obtain better value for patients. In particular, it called for a pricing scheme based on value for patients, ie effectiveness, rather than profit controls. The DoH, acknowledging the report's complexity, says it will take four principles into account in its negotiations during the forthcoming months: value for money, promoting innovation, assisting the uptake of new cost-effective medicines and promoting market stability. MHRA launches e-bulletin The MHRA (www.mhra.gov.uk) has next issue can be downloaded. The launched an electronic bulletin to August bulletin includes items on provide health professionals with antidepressants and suicide, updates about the safe use of medi-adverse effects of dopamine ago-cines. Users need to sign up to nists and information about smokreceive an e-mail alert when the ing cessation and isotretinoin. DURG call for abstracts The Drug Utilisation Research Group is calling for abstracts for its 19th annual meeting ,Target-driven medicine , is this the end of prescribing freedom?' to be held on 7 February 2008 at the Royal Society of Medicine, London. Abstracts are requested on any aspects of drug utilisation research. A bursary of £500 will be awarded for the best abstract received. The closing date for receipt of abstracts is 26 November. Further information about abstract submission is available at www.durg.org.uk. GP prescribing up by half Prescription volume and costs in England increased by approximately half over the decade to 2006, according to data published by the Information Centre for Health and Social Care (www.ic.nhs.uk). The number of items dispensed per year increased by 55 per cent and the cost by 60 per cent in real terms. The average number of items per head of population was 10.0 in 1996 and 14.8 in 2006; older people received 21.2 items per head in 1996 but 40.8 in 2006. MR morphines similar Modified-release preparations of morphine are equivalent in the treatment of severe pain, according to a new review by Bandolier (www.jr2.ox.ac.uk). The analysis of 54 randomised trials, which reviewed the release mechanisms and clinical data for four brands, showed these preparations provide effective analgesia for malignant and nonmalignant pain; about 4 per cent of patients were unable to tolerate the adverse effects of morphine. NSAIDs compared in OA Etoricoxib (Arcoxia) and naproxen are equally effective in the long-term treatment of osteoarthritis (Ann Rheum Dis 2007;66:945,51). Extension studies for two one-year trials showed that, after a total of 138 weeks, the two drugs had almost identical effects on pain and function assessments. All treatments were generally well tolerated, but serious cardiovascular effects were more common with etoricoxib and serious GI effects more common with naproxen. CPN nystatin allowed Community practitioner nurses (CPNs) may now prescribe oral nystatin (Nystan) to treat oral thrush in neonates, following a special amendment to the regulations limiting their prescribing to licensed indications. CPNs may now prescribe oral nystatin at the dose recommended in the BNF for Children provided they are sure of the diagnosis. In doing so, they accept clinical and medicolegal responsibility for their actions. There are no other exceptions to the prohibition of off-label prescribing. 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