186 resultados para rearranged (4 -> 2)-abeo-clerodane


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This article explores the relationship between the Responsibility to Protect (R2P) and the pursuit of the so-called ‘Women, Peace and Security’ (WPS) agenda at the UN. We ask whether the two agendas should continue to be pursued separately or whether each can make a useful contribution to the other. We argue that while the history of R2P has not included language that deliberately evokes the protection of women and the promotion of gender in preventing genocide and mass atrocities, this does not preclude the R2P and WPS agendas becoming mutually reinforcing. The article identifies cross-cutting areas where the two agendas may be leveraged for the UN and member states to address the concerns of women as both actors in need of protection and active agents in preventing and responding to genocide and mass atrocities, namely in the areas of early warning.

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This is an update of an earlier paper, and is written for Excel 2007. A series of Excel 2007 models is described. The more advanced versions allow solution of f(x)=0 by examining change of sign of function values. The function is graphed and change of sign easily detected by a change of colour. Relevant features of Excel 2007 used are Names, Scatter Chart and Conditional Formatting. Several sample Excel 2007 models are available for download, and the paper is intended to be used as a lesson plan for students having some familiarity with derivatives. For comparison and reference purposes, the paper also presents a brief outline of several common equation-solving strategies as an Appendix.

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This paper discusses how fundamentals of number theory, such as unique prime factorization and greatest common divisor can be made accessible to secondary school students through spreadsheets. In addition, the three basic multiplicative functions of number theory are defined and illustrated through a spreadsheet environment. Primes are defined simply as those natural numbers with just two divisors. One focus of the paper is to show the ease with which spreadsheets can be used to introduce students to some basics of elementary number theory. Complete instructions are given to build a spreadsheet to enable the user to input a positive integer, either with a slider or manually, and see the prime decomposition. The spreadsheet environment allows students to observe patterns, gain structural insight, form and test conjectures, and solve problems in elementary number theory.

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Quantum cascade laserabsorption spectroscopy was used to measure the absolute concentration of acetylene in situ during the nanoparticle growth in Ar + C2H2 RF plasmas. It is demonstrated that the nanoparticle growth exhibits a periodical behavior, with the growth cycle period strongly dependent on the initial acetylene concentration in the chamber. Being 300 s at 7.5% of acetylene in the gas mixture, the growth cycle period decreases with the acetylene concentration increasing; the growth eventually disappears when the acetylene concentration exceeds 32%. During the nanoparticle growth, the acetylene concentration is small and does not exceed 4.2% at radio frequency (RF) power of 4 W, and 0.5% at RF power of 20 W. An injection of a single acetylene pulse into the discharge also results in the nanoparticlenucleation and growth. The absorption spectroscopy technique was found to be very effective for the time-resolved measurement of the hydrocarbon content in nanoparticle-generatingplasmas.

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Strong electromagnetic field enhancement that occurs under conditions of the surface plasmon excitation in metallic nanoparticles deposited on a semiconductor surface is a very efficient and promising tool for increasing the optical absorption within semiconductor solar cells and, hence, their photocurrent response. The enhancement of the optical absorption in thin-film silicon solar cells via the excitation of localized surface plasmons in spherical silver nanoparticles is investigated. Using the effective medium model, the effect of the nanoparticle size and the surface coverage on that enhancement is analyzed. The optimum configuration and the nanoparticle parameters leading to the maximum enhancement in the optical absorption and the photocurrent response in a single p-n junction silicon cell are obtained. The effect of coupling between the silicon layer and the surface plasmon fields on the efficiency of the above enhancement is quantified as well.

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Twenty-three non-methane hydrocarbons were captured from the exhaust of a car operating on unleaded petrol (ULP) and 10% ethanol fuels at steady speed on a chassis dynamometer. The compounds were identified and quantified by GC/MS/FID and their emission concentrations at 60 km/h, 80km/h and idle speed were evaluated. The most abundant compounds in the exhaust included n-hexane, n-heptane, benzene, toluene, ethyl benzene, m- and p-xylenes, and methylcyclopentane. Because of the large number of compounds involved, no attempt was made to compare the emission concentrations of the compounds. Rather the sum of the emission concentrations for the suite of compounds identified was compared when the car was powered by ULP and 10% ethanol fuel. It was evident from the results that the emission concentrations and factors were generally higher with ULP than with 10% ethanol fuel. The total emission concentrations with the ULP fuel were 2.8, 4.2 and 2.6 times the corresponding values for the 10% ethanol fuel at 60km/h, 80km/h and idle speed, respectively. The implications of the results on the environment are discussed in the paper.

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A laboratory experiment was set up in small chambers for monitoring greenhouse gas emissions and determining the most suitable time for sampling. A six-treatment experiment was conducted, including a one week pre-incubation and a week for incubation. Timelines for sampling were 1, 2, 3, 6 and 24 hours after closing the lid of the incubation chambers. Variation in greenhouse gas fluxes was high due to the time of sampling. The rates of gas emissions increased in first three hours and decreased afterward. The rates of greenhouse gas emissions at 3 hours after closing lids was close to the mean for the 24-h period.

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Chronic wounds, such as venous and diabetic leg ulcers, represent a significant health and financial burden to individuals and healthcare systems. In worst case scenarios this condition may require the amputation of an affected limb, with significant impact on patient quality of life and health. Presently there are no clinical biochemical analyses used in the diagnosis and management of this condition; moreover few biochemical therapies are accessible to patients. This presents a significant challenge in the efficient and efficacious treatment of chronic wounds by medical practitioners. A number of protein-centric investigations have analysed the wound environment and implicated a suite of molecular species predicted to be involved in the initiation or perpetuation of the condition. However, comprehensive proteomic investigation is yet to be engaged in the analysis of chronic wounds for the identification of molecular diagnostic/prognostic markers of healing or therapeutic targets. This review examines clinical chronic wound research and recommends a path towards proteomic investigation for the discovery of medically significant targets. Additionally, the supplementary documents associated with this review provide the first comprehensive summary of protein-centric, small molecule and elemental analyses in clinical chronic wound research.

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Suspected nephrocarcinogenic effects of trichloroethene (TRI) in humans are attributed to metabolites derived from the glutathione transferase (GST) pathway. The influence of polymorphisms of GSTM1 and GSTT1 isoenzymes on the risk of renal cell cancer in subjects having been exposed to high levels of TRI over many years was investigated. GSTM1 and GSTT1 genotypes were determined by internal standard controlled polymerase chain reaction. Fourty-five cases with histologically verified renal cell cancer and a history of long-term occupational exposure to high concentrations of TRI were studied. A reference group consisted of 48 workers from the same geographical region with similar histories of occupational exposures to TRI but not suffering from any cancer. Among the 45 renal cell cancer patients, 27 carried at least one functional GSTM1 (GSTM1 +) and 18 at least one functional GSTT1 (GSTT1 +). Among the 48 reference workers, 17 were GSTM1 + and 31 were GSTT1 +. Odds ratios for renal cell cancer were 2.7 for GSTM1 + individuals (95% CI, 1.18-6.33; P < 0.02) and 4.2 for GSTT1 + individuals (95% CI, 1.16-14.91; P < 0.05), respectively. The data support the present concept of the nephrocarcinogenicity of TRI.

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Tobacco use is causally associated with head and neck squamous cell cancer (HNSCC). Here, we present the results of a case-control study that investigated the effects that the genetic variants of the cytochrome (CYP)1A1, CYP1B1, glutathione-S-transferase (GST)M1, GSTT1, and GSTP1 genes have on modifying the risk of smoking-related HNSCC. Allelisms of the CYP1A1, GSTT1, GSTM1, and GSTT1 genes alone were not associated with an increased risk. CYP1B1 codon 432 polymorphism was found to be a putative susceptibility factor in smoking-related HNSCC. The frequency of CYP1B1 polymorphism was significantly higher (P < 0.001) in the group of smoking cases when compared with smoking controls. Additionally, an odds ratio (OR) of 4.53 (2.62-7.98) was discovered when investigating smoking and nonsmoking cases for the susceptible genotype CYP1B1*2/*2, when compared with the presence of the genotype wild type. In combination with polymorphic variants of the GST genes, a synergistic-effect OR was observed. The calculated OR for the combined genotype CYP1B1*2/*2 and GSTM1*2/*2 was 12.8 (4.09-49.7). The calculated OR for the combined genotype was 13.4 (2.92-97.7) for CYP1B1*2/*2 and GSTT1*2/*2, and 24.1 (9.36-70.5) for the combination of CYP1B1*2/*2 and GSTT1-expressors. The impact of the polymorphic variants of the CYP1B1 gene on HNSCC risk is reflected by the strong association with the frequency of somatic mutations of the p53 gene. Smokers with susceptible genotype CYP1B1*2/*2 were 20 times more likely to show evidence of p53 mutations than were those with CYP1B1 wild type. Combined genotype analysis of CYP1B1 and GSTM1 or GSTT1 revealed interactive effects on the occurrence of p53 gene mutations. The results of the present study indicate that polymorphic variants of CYP1B1 relate significantly to the individual susceptibility of smokers to HNSCC.

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Optically tuned silver nanoparticles (AgNP's) functionalized with ω-mercaptoalkanoic acids are synthesized and used as a signal amplifier for the surface-enhanced resonance Raman scattering (SERRS) study of heme cofactor in methemoglobin (metHb). Even though both mercaptopropionic acid (MPA)- and mercaptononanoic acid (MNA)-functionalized AgNP's exemplify vastly enhanced SERRS signal of metHb, MNA-AgNP's amplify the SERRS signal amid preservation of the nativity of the heme pocket, unlike MPA-AgNP's. The electrostatic interaction between MNA-AgNP's and metHb leads to instant signal enhancement with a Raman enhancement factor (EF(SERS)) of 4.2 × 10(3). Additionally, a Langmuir adsorption isotherm has been employed for the adsorption of metHb on the MNA-AgNP surface, which provides the real surface coverage and equilibrium constant (K) of metHb as 139 nM and 3.6 × 10(8) M(-1), respectively. The lowest detection limit of 10 nM for metHb has been demonstrated using MNA-AgNP's besides retaining the nativity of the heme pocket.

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This study evaluated the physiological tolerance times when wearing explosive and chemical (>35kg) personal protective equipment (PPE) in simulated environmental extremes across a range of differing work intensities. Twelve healthy males undertook nine trials which involved walking on a treadmill at 2.5, 4 and 5.5 km.h-1 in the following environmental conditions, 21, 30 and 37 °C wet bulb globe temperature (WBGT). Participants exercised for 60 min or until volitional fatigue, core temperature reached 39 °C, or heart rate exceeded 90% of maximum. Tolerance time, core temperature, skin temperature, mean body temperature, heart rate and body mass loss were measured. Exercise time was reduced in the higher WBGT environments (WBGT37

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Background: Type 2 diabetes affects an estimated 347 million people worldwide and often leads to serious complications including blindness, kidney disease, and limb amputation. Comorbid dysphoria is common and is an independent risk factor for poor glycaemic control. Professional support for diabetes self-management and dysphoria has limited availability and involves high costs, especially after regular hours, and in rural and remote areas. Web-based cognitive behavior therapy offers highly accessible, acceptable, and cost-effective support for people with diabetes. This paper describes the development of OnTrack Diabetes, a self-guided, Web-based program to promote improved physical and emotional self-management in people with Type 2 diabetes. Objective: The objective of the study is to describe the development of the OnTrack Diabetes program, which is a self-guided, Web-based program aimed to promote euthymia and improved disease self-management in people with Type 2 diabetes. Methods: Semistructured interviews with 12 general practitioners and 13 patients with Type 2 diabetes identified enablers of and barriers to effective diabetes self-management, requirements for additional support, and potential program elements. Existing resources and research data informed the development of content, and consultants from relevant disciplines provided feedback on draft segments and reviewed the program before release. Using a self-guided delivery format contained costs, in addition to adapting program features and modules from an existing OnTrack program. Results: A separate paper describes the protocol for a randomized controlled trial to provide this required evaluation. Conclusions: Development of the OnTrack Diabetes program demonstrates strategies that help ensure that a program is acceptable to users. The next stages involve testing users’ experiences and examining the program’s effectiveness and cost-effectiveness in randomized controlled trials.

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Purpose – There is limited evidence on how differences in economic environments affect the demand for and supply of auditing. Research on audit pricing has mainly focused on large client markets in developed economies; in contrast, the purpose of this paper is to focus on the small client segment in the emerging economy of Thailand which offers a choice between auditors of two different qualities. Design/methodology/approach – This paper is based on a random stratified sample of small clients in Thailand qualifying for audit exemption. The final sample consists of 1,950 firm-year observations for 2002-2006. Findings – The authors find evidence of product differentiation in the small client market, suggesting that small firms view certified public accountants as superior and pay a premium for their services. The authors also find that audit fees have a positive significant association with leverage, metropolitan location and client size. Audit risk and audit opinion are not, however, significantly associated with audit fees. Furthermore, the authors find no evidence that clients whose financial year ends in the auditors’ busy period pay significantly higher audit fees, and auditors engage in low-balling on initial engagements to attract audit clients. Research limitations/implications – The research shows the importance of exploring actual decisions regarding audit practice and audit pricing in different institutional and organizational settings. Originality/value – The paper extends the literature from developed economies and large/listed market setting to the emerging economy and small client market setting. As far as the authors are aware, this is the first paper to examine audit pricing in the small client market in an emerging economy.

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Background Anxiety disorders and major depressive disorder (MDD) are common and disabling mental disorders. This paper aims to test the hypothesis that common mental disorders have become more prevalent over the past two decades. Methods We conducted a systematic review of prevalence, remission, duration, and excess mortality studies for anxiety disorders and MDD and then used a Bayesian meta-regression approach to estimate point prevalence for 1990, 2005, and 2010. We also conducted a post-hoc search for studies that used the General Health Questionnaire (GHQ) as a measure of psychological distress and tested for trends to present a qualitative comparison of study findings. Results This study found no evidence for an increased prevalence of anxiety disorders or MDD. While the crude number of cases increased by 36%, this was explained by population growth and changing age structures. Point prevalence of anxiety disorders was estimated at 3.8% (3.6-4.1%) in 1990 and 4.0% (3.7-4.2%) in 2010. The prevalence of MDD was unchanged at 4.4% in 1990 (4.2-4.7%) and 2010 (4.1-4.7%). However, 8 of the 11 GHQ studies found a significant increase in psychological distress over time. Conclusions The perceived "epidemic" of common mental disorders is most likely explained by the increasing numbers of affected patients driven by increasing population sizes. Additional factors that may explain this perception include the higher rates of psychological distress as measured using symptom checklists, greater public awareness, and the use of terms such as anxiety and depression in a context where they do not represent clinical disorders.