39 resultados para Financial and concentration indexes
Resumo:
Room temperature ionic liquids have been used as solvents for the palladium-catalysed copolymerisation of styrene and carbon monoxide. The behaviour of various ionic liquids, the nature and concentration of palladium catalyst, and the reusability of the catalyst-ionic liquid system are discussed. The effects of cation, anion and alkyl chain length of the ionic liquids on the reaction are also addressed. The yield of the polyketone in the ionic liquid systems is enhanced over conventional solvents studied under similar conditions.
Resumo:
Dipeptidyl peptidase IV (DPP IV) is the primary inactivator of glucoregulatory incretin hormones. This has lead to development of DPP IV inhibitors as a new class of agents for the treatment of type 2 diabetes. Recent reports indicate that other antidiabetic drugs, such as metformin, may also have inhibitory effects on DPP IV activity. In this investigation we show that high concentrations of several antidiabetic drug classes, namely thiazolidinediones, sulphonylureas, meglitinides and morphilinoguanides can inhibit DPP IV The strongest inhibitor nateglinide, the insulin-releasing meglitinide was effective at low therapeutically relevant concentrations as low as 25 mu mol/l. Nateglinide also prevented the degradation of glucagon-like peptide-1 (GLP-1) by DPP IV in a time and concentration-dependent manner. In vitro nateglinide and GLP-1 effects on insulin release were additive. In vivo nateglinide improved the glucose-lowering and insulin-releasing activity of GLP-1 in obese-diabetic ob/ob mice. This was accompanied by significantly enhanced circulating concentrations of active GLP-1(7-36)amide and lower levels of DPP IV activity. Nateglinide similarly benefited the glucose and insulin responses to feeding in ob/ob mice and such actions were abolished by coadministration of exendin(9-39) and (Pro(3))GIP to block incretin hormone action. These data indicate that the use of nateglinide as a prandial insulin-releasing agent may partly rely on inhibition of GLP-1 degradation as well as beta-cell K-ATP channel inhibition. (C) 2007 Elsevier B.V. All rights reserved.
Resumo:
Nine non-nematode-derived double-stranded RNAs (dsRNAs), designed for use as controls in RNA interference (RNAi) screens of neuropeptide targets, were found to induce aberrant phenotypes and an unexpected inhibitory effect on motility of root knot nematode Meloidogyne incognita J2s following 24 h soaks in 0.1 mg/ml dsRNA; a simple soaking procedure which we have found to elicit profound knockdown of neuronal targets in Globodera pallida J2s. We have established that this inhibitory phenomenon is both time- and concentration-dependent, as shorter 4 h soaks in 0.1 mg/ml dsRNA had no negative impact on M. incognita J2 stage worms, yet a 10-fold increase in concentration to 1 mg/ml for the same 4 h time period had an even greater qualitative and quantitative impact on worm phenotype and motility. Further, a 10-fold increase of J2s soaked in 0.1 mg/ml dsRNA did not significantly alter the observed phenotypic aberration, which suggests that dsRNA uptake of the soaked J2s is not saturated under these conditions. This phenomenon was not initially observed in potato cyst nematode G. pallida J2s, which displayed no aberrant phenotype, or diminution of migratory activity in response to the same 0.1 mg/ml dsRNA 24 h soaks. However, a 10-fold increase in dsRNA to 1 mg/ml was found to elicit comparable irregularity of phenotype and inhibition of motility in G. pallida, to that initially observed in M. incognita following a 24 h soak in 0.1 mg/ml dsRNA. Again, a 10-fold increase in the number of G. pallida J2s soaked in the same volume of 1 mg/ml dsRNA preparation did not significantly affect the observed phenotypic deviation. We do not observe any global impact on transcript abundance in either M. incognita or G. pallida J2s following 0.1 mg/ml dsRNA soaks, as revealed by reverse transcriptase-PCR and quantitative PCR data. This study aims to raise awareness of a phenomenon which we observe consistently and which we believe signifies a more expansive deficiency in our knowledge and understanding of the variables inherent to RNAi-based investigation.
Resumo:
This work explores the effects of argon and nitrogen, two electrochemically and chemically inert gases frequently used in sample preparation of room temperature ionic liquid (RTIL) solutions, on the eelectrochemical characterization of ferrocene (Fc) dissolved in the RTIL 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C(2)mim][NTf2]). Remarkably, chronoamperometrically determined diffusion coefficients of Fc in [C(2)mim][NTf2] are found to increase from 4.8 (+/- 0.2) x 10(-11) m(2) s(-1) under vacuum conditions to 6.6 (+/- 0.5) x 10(-11) m(2) s(-1) in an atmosphere of 1 atm Ar. In contrast, exposing a vacuum-purified sample to an atmosphere of 1 atm N-2 resulted in no significant change in the measured diffusion coefficient of Fc. The effect of dissolved argon on diffusion transport is unexpected and has implications in electrochemistry and elsewhere. Fc was found to volatilize under vacuum conditions. We propose, however, that evacuation of the cell by vacuum prior to electrochemical measurements being carried out is the only way to ensure that no contamination of the sample occurs, and use of an in situ method of determining the diffusion coefficient and concentration of Fc dispells,any ambiguity associated with Fc depletion by vacuum.
Resumo:
Background:
Increasing the activity of defective cystic fibrosis transmembrane conductance regulator (CFTR) protein is a potential treatment for cystic fibrosis.
Methods:
We conducted a randomized, double-blind, placebo-controlled trial to evaluate ivacaftor (VX-770), a CFTR potentiator, in subjects 12 years of age or older with cystic fibrosis and at least one G551D-CFTR mutation. Subjects were randomly assigned to receive 150 mg of ivacaftor every 12 hours (84 subjects, of whom 83 received at least one dose) or placebo (83, of whom 78 received at least one dose) for 48 weeks. The primary end point was the estimated mean change from baseline through week 24 in the percent of predicted forced expiratory volume in 1 second (FEV1).
Results:
The change from baseline through week 24 in the percent of predicted FEV1 was greater by 10.6 percentage points in the ivacaftor group than in the placebo group (P < 0.001). Effects on pulmonary function were noted by 2 weeks, and a significant treatment effect was maintained through week 48. Subjects receiving ivacaftor were 55% less likely to have a pulmonary exacerbation than were patients receiving placebo, through week 48 (P < 0.001). In addition, through week 48, subjects in the ivacaftor group scored 8.6 points higher than did subjects in the placebo group on the respiratory-symptoms domain of the Cystic Fibrosis Questionnaire-revised instrument (a 100-point scale, with higher numbers indicating a lower effect of symptoms on the patient's quality of life) (P < 0.001). By 48 weeks, patients treated with ivacaftor had gained, on average, 2.7 kg more weight than had patients receiving placebo (P < 0.001). The change from baseline through week 48 in the concentration of sweat chloride, a measure of CFTR activity, with ivacaftor as compared with placebo was -48.1 mmol per liter (P < 0.001). The incidence of adverse events was similar with ivacaftor and placebo, with a lower proportion of serious adverse events with ivacaftor than with placebo (24% vs. 42%).
Conclusions:
Ivacaftor was associated with improvements in lung function at 2 weeks that were sustained through 48 weeks. Substantial improvements were also observed in the risk of pulmonary exacerbations, patient-reported respiratory symptoms, weight, and concentration of sweat chloride.
Resumo:
The synthesis and in vitro evaluation of four cationic lipid gene delivery vectors, characterized by acyclic or macrocyclic, and saturated or unsaturated hydrophobic regions, is described. The synthesis employed standard protocols, including ring-closing metathesis for macrocyclic lipid construction. All lipoplexes studied, formulated from plasmid DNA and a liposome composed of a synthesized lipid, 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine (EPC), and either 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) or cholesterol as co-lipid, exhibited plasmid DNA binding and protection from DNase I degradation, and concentration dependent cytotoxicity using Chinese hamster ovary-K1 cells. The transfection efficiency of formulations with cholesterol outperformed those with DOPE, and in many cases the EPC/cholesterol control, and formulations with a macrocyclic lipid (+/- 10:1) outperformed their acyclic counterparts (+/- 3:1).
Resumo:
Young adults in the UK are increasingly dependent on family support to offset the costs of living independently. This article explores these complex intergenerational exchanges from the perspective of a group of single young adults in their mid-twenties to mid-thirties who had been in receipt of various forms of financial and material support from family members since leaving the parental home. We outline the nature of this support and then consider how these forms of assistance are understood by those in receipt of them. We conclude that the co-existence of a sense of both gratitude and discomfort which is often generated by these exchanges is managed but by no means resolved by a blurring of the boundaries between gifts and loans, a set of negotiations which may not even be an option amongst less advantaged young adults.
Resumo:
PURPOSE: Peptide YY (PYY) is a gastrointestinal hormone with physiological actions regulating appetite and energy homoeostasis. The cellular mechanisms by which nutrients stimulate PYY secretion from intestinal enteroendocrine cells are still being elucidated.
METHODS: This study comprehensively evaluated the suitability of intestinal STC-1 cells as an in vitro model of PYY secretion. PYY concentrations (both intracellular and in culture media) with other intestinal peptides (CCK, GLP-1 and GIP) demonstrated that PYY is a prominent product of STC-1 cells. Furthermore, acute and chronic PYY responses to 15 short (SCFAs)- and long-chain (LCFAs) dietary fatty acids were measured alongside parameters for DNA synthesis, cell viability and cytotoxicity.
RESULTS: We found STC-1 cells to be reliable secretors of PYY constitutively releasing PYY into cell culture media (but not into non-stimulatory buffer). We demonstrate for the first time that STC-1 cells produce PYY mRNA transcripts; that STC-1 cells produce specific time- and concentration-dependent PYY secretory responses to valeric acid; that linoleic acid and conjugated linoleic acid 9,11 (CLA 9,11) are potent PYY secretagogues; and that chronic exposure of SCFAs and LCFAs can be detrimental to STC-1 cells.
CONCLUSIONS: Our studies demonstrate the potential usefulness of STC-1 cells as an in vitro model for investigating nutrient-stimulated PYY secretion in an acute setting. Furthermore, our discovery that CLA directly stimulates L-cells to secrete PYY indicates another possible mechanism contributing to the observed effects of dietary CLA on weight loss.
Resumo:
The M17 leucine aminopeptidase of the intraerythrocytic stages of the malaria parasite Plasmodium falciparum (PfLAP) plays a role in releasing amino acids from host hemoglobin that are used for parasite protein synthesis, growth, and development. This enzyme represents a target at which new antimalarials could be designed since metalloaminopeptidase inhibitors prevent the growth of the parasites in vitro and in vivo. A study on the metal ion binding characteristics of recombinant P. falciparum M17 leucine aminopeptidase (rPfLAP) shows that the active site of this exopeptidase contains two metal-binding sites, a readily exchangeable site (site 1) and a tight binding site (site 2). The enzyme retains activity when the metal ion is removed from site 1, while removal of metal ions from both sites results in an inactive apoenzyme that cannot be reactivated by the addition of divalent metal cations. The metal ion at site 1 is readily exchangeable with several divalent metal ions and displays a preference in the order of preference Zn(2+) > Mn(2+) > Co(2+) > Mg(2+). While it is likely that native PfLAP contains a Zn(2+) in site 2, the metal ion located in site 1 may be dependent on the type and concentration of metal ions in the cytosolic compartment of the parasite. Importantly, the type of metal ion present at site 1 influences not only the catalytic efficiency of the enzyme for peptide substrates but also the mode of binding by bestatin, a metal-chelating inhibitor of M17 aminopeptidases with antimalarial activity.
Resumo:
We present in this study the effect of nature and concentration of lithium salt, such as the lithium hexafluorophosphate, LiPF6; lithium tris(pentafluoroethane)-trifluorurophosphate LiFAP; lithium bis(trifluoromethylsulfonyl)imide, LiTFSI, on the CO2 solubility in four electrolytes for lithium ion batteries based on pure solvent that include ethylene carbonate (EC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), as well as, in the EC:DMC, EC:EMC and EC:DEC (50:50) wt.% binary mixtures as a function of temperature from (283 to 353) K and atmospheric pressure. Based on experimental solubility values, the Henry’s law constant of the carbon dioxide in these solutions with the presence or absence of lithium salt was then deduced and compared with reported values from the literature, as well as with those predicted by using COSMO-RS methodology within COSMOThermX software. From this study, it appears that the addition of 1 mol · dm-3 LiPF6 salt in alkylcarbonate solvents decreases their CO2 capture capacity. By using the same experimental conditions, an opposite CO2 solubility trend was generally observed in the case of the addition of LiFAP or LiTFSI salts in these solutions. Additionally, in all solutions investigated during this work, the CO2 solubility is greater in electrolytes containing the LiFAP salt, followed by those based on the LiTFSI case. The precision and accuracy of the experimental data reported therein, which are close to (1 and 15)%, respectively. From the variation of the Henry’s law constant with temperature, the partial molar thermodynamic functions of dissolution such as the standard Gibbs energy, the enthalpy, and the entropy, as well as the mixing enthalpy of the solvent with CO2 in its hypothetical liquid state were calculated. Finally, a quantitative analysis of the CO2 solubility evolution was carried out in the EC:DMC (50:50) wt.% binary mixture as the function of the LiPF6 or LiTFSI concentration in solution to elucidate how ionic species modify the CO2 solubility in alkylcarbonates-based Li-ion electrolytes by investigating the salting effects at T = 298.15 K and atmospheric pressure.
Resumo:
This paper aims to provide a critical analysis of the role of support in teenage motherhood. Family, partner and peer support are considered and literature emanating from both the USA and UK is reviewed. In summary the research literature indicates that family support is particularly important to teenage mothers and has been found to have a positive influence on parenting behaviours and practices. However, the mother–daughter relationship is not always a straightforward one and conflict between the two can diminish some of the positive impact. The research on partner support highlights how support from fathers and/or other male partners has been linked with improved financial and psychological outcomes for teenage mothers as well as having a positive influence on parenting behaviours. There is also evidence to suggest that support from partners may become increasingly important to teenage mothers over time and can be a valuable source of socializing participation and positive feedback. While the research available on peer support is much more limited it suggests that the emotional support of peers is perceived as being important by teenage mothers. Current research findings suggest that families, partners and peers tend to provide different, but complementary, forms of support for teenage mothers which, on the whole, appear to contribute to more positive outcomes for this group.
Resumo:
Purpose – Informed by the work of Laughlin and Booth, the paper analyses the role of accounting and accountability practices within the 15th century Roman Catholic Church, more specifically within the Diocese of Ferrara (northern Italy), in order to determine the presence of a sacred-secular dichotomy. Pope Eugenius IV had embarked upon a comprehensive reform of the Church to counter the spreading moral corruption within the clergy and the subsequent disaffection with the Church by many believers. The reforms were notable not only for the Pope’s determination to restore the moral authority and power of the Church but for the essential contributions of ‘profane’ financial and accounting practices to the success of the reforms.
Design/methodology/approach – Original 15th century Latin documents and account books of the Diocese of Ferrara are used to highlight the link between the new sacred values imposed by Pope Eugenius IV’s reforms and accounting and accountability practices.
Findings – The documents reveal that secular accounting and accountability practices were not regarded as necessarily antithetical to religious values, as would be expected by Laughlin and Booth. Instead, they were seen to assume a role which was complementary to the Church’s religious mission. Indeed, they were essential to its sacred mission during a period in which the Pope sought to arrest the moral decay of the clergy and reinstate the Church’s authority. Research implications/limitations – The paper shows that the sacred-secular dichotomy cannot be considered as a priori valid in space and time. There is also scope for examining other Italian dioceses where there was little evidence of Pope Eugenius’ reforms.
Originality/value – The paper presents a critique of the sacred-secular divide paradigm by considering an under-researched period and a non Anglo-Saxon context.
Resumo:
Financial and cultural aspects of corporate giving by UK and non-UK companies in response to the December 2004 South Asia Tsunami disaster are explored in this article. Literatures on corporate giving rationales, concepts of disaster and donor activity in disasters provide an underpinning. The article seeks to make connections between this high profile if short-lived business giving and the funding of the arts that is sought from business; and to draw tentative lessons for arts funding when seeking business support. The giving accounts in the wake of the Tsunami from a non-probability sample of 56 UK companies and 16 non-UK companies were examined. Reported online to the UK charity Business in the Community, these accounts were accessed in February 2005 and scrutinized thematically. Concurrently, company financial profiles to accompany giving figures were constructed. Although linkages between donation levels and financial performance were lacking, emerging themes included the role of employees, influencing company giving and creating a climate of expectation of firms' contributions. These developments may have important implications for business funding for the arts, where leading philanthropists are prominent as individuals in the giving landscapes; but employees' collective involvement is not marked. Alternatively, cultivation of employees as would-be donors, indirectly via their firms, may be a more secure, if lower level route to funding for some arts organizations than dependence on high profile business leaders. The article considers alternative scenarios for company giving in disaster contexts, including as a sustained and lasting giving theme or as company support as a ‘one-off’ event, rock-star style. The likely development of employee power as a key element in company giving is explored; and its wider meanings for funding in arts settings, (where the giver as rock star heroine/hero is also prominent) are considered.
Resumo:
Falls are a significant threat to the safety, health and independence of older citizens. Despite the substantial evidence that is available around effective falls prevention programmes and interventions, their translation into falls reduction programmes and policies has yet to be fully realised. While hip fracture rates are decreasing, the number and incidence of fall-related hospital admissions among older people continue to rise. Given the demographic trends that highlight increasing numbers of older people in the UK, which is broadly reflected internationally, there is a financial and social imperative to minimise the rate of falls and associated injuries. Falling is closely aligned to growing older (Slips, Trips and Falls Update: From Acute and Community Hospitals and Mental Health Units in England and Wales, Department of Health, HMSO, London, 2010). According to the World Health Organization, around 30% of older people aged over 65 and 50% of those over 80 will fall each year (Falls Fact Sheet Number 344, WHO, Geneva, 2010). Falls happen as a result of many reasons and can have harmful consequences, including loss of mobility and independence, confidence and in many cases even death (Cochrane Database Syst Rev 15, 2009, 146; Slips, Trips and Falls Update: From Acute and Community Hospitals and Mental Health Units in England and Wales, Department of Health, HMSO, London, 2010; Falling Standards, Broken Promises: Report of the National
Audit of Falls and Bone Health in Older People 2010, Health Care Quality
Improvement Partnership, London, 2011). What is neither fair nor correct is the
common belief by old and young alike that falls are just another inconvenience to put up with. The available evidence justifiably supports the view that well-organised services, based upon national standards and expert guidance, can prevent future falls among older people and reduce death and disability from fractures. This paper will draw from the UK, as an exemplar for policy and practice, to discuss the strategic direction of falls prevention programmes for older people and the partnerships that need to exist between researchers, service providers and users of services to translate evidence to the clinical setting. Second, it will propose some mechanisms for disseminating evidence to healthcare professionals and other stakeholders, to improve the quality and capacity of the clinical workforce.
Resumo:
A basic intuition is that arbitrage is easier when markets are most liquid. Surprisingly, we find that momentum profits are markedly larger in liquid market states. This finding is not explained by variation in liquidity risk, time-varying exposure to risk factors, or changes in macroeconomic condition, cross-sectional return dispersion, and investor sentiment. The predictive performance of aggregate market illiquidity for momentum profits uniformly exceed that of market return and market volatility states. While momentum strategies are unconditionally unprofitable in US, Japan, and Eurozone countries in the last decade, they are substantial following liquid market states.