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Acanthopanax senticosus extract with excessive standard of Pb, Cd, Hg, and Cu was used as the research object, and the alkyl thiourea functionalised silica was used as a new heavy metal removal scavenger. The heavy metal removal process was optimised by orthogonal experiment with dynamic and static adsorption modes. Meanwhile, the content of Acanthopanax B and Acanthopanax E, the solid content, and the HPLC fingerprint similarity were used as quality monitoring indicators of Acanthopanax senticosus heavy metal removal before and after. Then, the technical adaptability of heavy metal removal by alkyl thiourea functionalised silica was evaluated. Under the optimal dynamic adsorption conditions, the average removal rates of Pb, Cd, Hg, and Cu were 91.64%, 93.04%, 81.77%, and 83.11%, respectively. Under the optimal static adsorption conditions, the average removal rates of Pb, Cd, Hg, and Cu were 82.22%, 89.95%, 81.26%, and 82.97%, respectively. During Acanthopanax senticosus extract heavy metal removal before and after, the change percentage of Acanthopanax B and Acanthopanax E was less than 2.00%, the solid content loss rate was only 0.18%, and the fingerprint similarity was over 99.9%. The method can be used to satisfy the high efficiency of selective removal of harmful elements in Acanthopanax senticosus extract and the effective composition of almost no effect; the method is simple and easy, so it can be recommended for pretreatment of heavy metals in Traditional Chinese Medicine extracts, and this way provides a new thought and research technique to decrease the contents of heavy metals. more...

The influence of four parameters (temperature, scavenging time, amount of scavenger, and concentration of palladium in the solution) on the efficiency of Pd removal from a cross-coupling reaction, using a commercially available Pd scavenger, SPM32, was studied. The DoE-based method employed yielded more information than is readily attainable from standard adsorption isotherms and kinetics experiments. The optimal regime of scavenging was identified; intuitive and nonintuitive effects of temperature, scavenging time, and scavenger amounts were highlighted; and a mathematical model quantifying predicted Pd removal from the synthetic intermediate was built. more...

Dispersion corrected density functional theory (DFT-D) has been applied to understand the performance of several palladium metal scavengers. Nine different sulfur-based ligands and three different palladium metal sets have been investigated in detail. Based on a thorough analysis of the thermodynamic binding parameters ΔH, ΔG and ΔS, we have identified the best binding modes for all scavenger ligands. Bis-monodentate coordination is favoured over chelation in ΔH and ΔG values for most of the scavenger ligands. Special attention has been paid to the ligand strain energies, which account for the structural changes of the ligands upon complexation indicating that small (5-membered) chelates are considerably less favourable than expected. Some ligands can use their longest chain (>7-atoms) to yield trans chelates, which ligands with shorter chains (≤6-atoms) are unable to form. A secondary amino nitrogen (RR′NH) is found to be the best donor with highest binding enthalpy for Pd(ii) metal systems. In terms of the strength of the initial binding interactions, -SMe > -SH; capping thiols (-SH) as thioethers (-SMe) is therefore suggested to be an effective strategy in scavenger design. These observations mark the beginning of a knowledge base of the full range of possible interactions, leading to the construction of a sulfur ligand database for the design of scavenger systems. more...

Access to psychiatric services for homeless mentally ill people Christopher North's reply Ethical and legal issues in suicide Judi Davis replies

We describe efforts to achieve a multigram synthesis of the tricyclic spiroacetal core of the lituarines based on the addition of acyl anion equivalent to 4-(2-furyl)butan-2-one (18). We report the first cases of chemoselective Achmatowicz reaction in the presence of a second furan ring that lacks an α-hydroxyl group. The use of lithiated methoxyallene provides an efficient one-step conversion of ketone 18 into a tricyclic Diels-Alder adduct (27). In the final route, asymmetric cyanosilylation of ketone 29 achieved the construction of the stereogenic C(12) 3°-alcohol centre. Subsequent butenylation, diastereoselective reduction of keto-alcohol (+)-33 and alkene cross metathesis set up an oxy-Michael reaction to close the C(8-12) tetrahydropyran ring. The second ring-closure, which completed the route, was achieved by oxidative spirocyclisation following our earlier work. © 2011 Elsevier Ltd. All rights reserved. more...

Familial combined hyperlipidaemia (FCHL) is a complex genetic disorder conferring high risk of premature atherosclerosis, characterized by high cholesterol and/or triglyceride, low high density lipoprotein (HDL) cholesterol and insulin resistance. We examined whether pioglitazone, added to conventional lipid-lowering therapy, would favourably affect metabolic parameters and alter body fat content. We undertook a randomized, double blind, placebo-controlled study in 22 male patients with FCHL treated with pioglitazone or matching placebo 30 mg daily for 4 weeks, increasing to 45 mg for 12 weeks. Magnetic resonance imaging and proton magnetic resonance spectroscopy were performed to measure adipose tissue (AT) body content as well as intrahepatocellular lipids (IHCL) and intramyocellular lipids (IMCL) at baseline and after treatment. Significantly improved in the pioglitazone group were: triglyceride/HDL (atherogenic index of plasma) -32.3% (p=0.002), plasma glucose -4.4% (p=0.03), alanine-aminotransferase (ALT) -7.7% (p=0.005) and adiponectin 130.1% (p=0.001). Pioglitazone treatment resulted in a significant increase in total (5.3%, p=0.02) and subcutaneous (7.1%, p=0.003) adipose tissue as well as in soleus-IMCL levels (47.4%, p=0.02) without alteration in intra-abdominal AT or IHCL. Changes in ALT and AST and IHCL were strongly correlated (r=0.72, p more...

Historically, psychologists have expressed concern about the overreliance on undergraduates as research participants in the discipline. Moreover, the last 25 years have witnessed a boom in research on adolescence as a time of continuing developmental change in a variety of domains and significant life transitions. Given the above criticism and new prolific area of research, the present study examines whether employing undergraduates as a surrogate adult sample has decreased in the psychology literature since the mid-1970s. All articles published in six prestigious journals (representing five subdivisions of psychology) were investigated for 1975, 1985, and 1995. Of the 1,719 articles coded, 68.31 % were found to employ undergraduates exclusively as subjects. There were no significant decreases in the use of undergraduate research participants from 1975 to 1995. Other methodological problems, including reports of descriptive statistics for age, recruiting techniques, and statements referring to the limited generalizability of the findings, are also examined. As we put closure on the 20th century, psychologists can be proud of a discipline that has thrived and flourished. However, as the discipline strives to maturity, one area of concern has been the need to address poignant criticisms of the use of undergraduate students as the predominant research participants in the field. To date we have witnessed criticisms of the over-use of undergraduate participants (e.g., chronologically, Christie, 1965; Smart, 1966; Adelson, 1969; Schultz, 1969; Higbee & Wells; 1972), the accumulated evidence that undergraduate students are neither representative of adults, adolescents, or the university population collectively, and the burgeoning developmental research on adolescence. The present paper assesses whether these criticisms and empirical findings have been assimilated into the general practice of employs ing undergraduates as research participants in psychology studies over the past 20-25 years. Historical Trends Concerning Undergraduates as Research Participants Concerns about an inappropriate reliance on undergraduate research participants emerged in 1965 (See Table 1 for a summary). Christie (1965) reported in the Journal of Abnormal and Social Psychology (jAsp) that the proportion of studies with undergraduate participants for the years 1949 to 1959 had more than doubled (increasing from 20% to 49%). Smart (1966) believed the overuse of undergraduate research participants should prompt researchers to ask themselves if they know what is "going on, psychologically, in the big world beyond the university" (p. 121). Other psychologists asserted that "college students are hardly a random sample of all humanity" (Myers, 1983, p. 32). Although some psychologists believe "that many research areas (e.g., perception) produce outcomes relatively unaffected by the special characteristics of college students" (Goodwin, 1995, p. 144), questions regarding the external validity of the research relying on undergraduate participants remain. The previous investigations of the contents of psychological journals varied in focus. Some analyzed particular journals (e.g., West, Newsom, & Fenaughty, 1992), whereas others analyzed specific topics across multiple journals (e.g., Wiesenthal, Edwards, Endler, Koza, Walton, & Emmott, 1978). Interestingly, the majority of journal investigations focused specifically on the subdisciplines of personality or social psychology (cf. Endler & Speer, 1998; Higbee & Wells, 1972; Reis & Stiller, 1992; Schultz, 1969; Sears, 1986; Smart, 1966). Though these investigations recorded the use of undergraduate research participants, the articles embraced separate agendas, varied in the journals examined, and covered different time intervals. Collectively, they do not provide an over-view of whom psychologists are studying across psychology's multiple subdisciplines. … more...

Optically active 2,5-disubstituted-cyclohexen-2-one derivatives have been prepared in a one-pot process consisting of five reaction steps: an organocatalytic asymmetric conjugated addition of beta-ketoesters to alpha,beta-unsaturated aldehydes that proceeds in aqueous solutions or under solvent-free conditions has been implemented in a multi-step process. more...

Christopher North with his wife Marisa run the Almassera Vella Arts Centre in a mountain village near Alicante, Spain (www.oldolivepress.com). He facilitates poetry readings , writing workshops and 7 day residential courses in the Spring and Autumn. His pamphlet collection A Mesh of Wires (Smith Doorstop 1999) was shortlisted for the Forward Prize, he had a third place in the National (1995) and recently won the Silver Wyvern at the ‘Poetry on the Lake' Festival in Italy. His first full collection Explaining the Circumstances was published by Oversteps Books in February 2010 (www.overstepsbooks.com). A bi-lingual joint collection with the poet Terry Gifford The Other Side of Aguilar is published this year. more...