Is the release of noradrenaline necessary for self-stimulation of the brain?

A totally voluntary plasmapheresis program recruits 900 individual donors per year at a cancer institute, where 500 to 900 units of platelets are transfused each month. Staff and donors use a film and brochures to recruit donors from the local community. Television and radio spots, with donor recognition pins, certificates, receptions, and picnics are utilized. Donor motivation was studied by use of: 1) California Psychological Inventory--measures a variety of "normal" personality traits; 2) Study of values--measures theoretical, economic, aesthetic, social, political, religious values; 3) Internal-External Control Scale--measures degree to which a person blames self vs. external events for what happens to him; 4) Faith in People Scale--measures individual's confidence in his fellow man; 5) Anomia Scale--measure of feelings of self-to-others alienation; 6) Mach IV Scale--measure of persons tendency to manipulate others; and 7) Biographical Data Form. Results are presented for 25 male donor subjects studied, as they compare with normative data for the scales used. Donors appeared to have the same traits as do the general population, but appeared lower in Machiavellianism than non-plasmapheresis donors. Prospective study plans include additional subjects to provide appropriate control groups.     

Effect of phenyl phosphorodiamidate on the fate of urea applied to wetland rice fields

The effect of phenyl phosphorodiamidate (PPD) on floodwater properties, N uptake,¹⁵N recovery, and grain yield of wetland rice (Oryza sativa L.) was evaluated in a series of field studies conducted at Muñoz and Los Baños, Philippines. Prilled urea and PPD-amended urea were applied to soil and incorporated immediately prior to transplanting or applied to floodwater after transplanting. Urea was also deep-placed or added in a coated form in two studies.The addition of PPD with urea retarded urea hydrolysis by 1–3 days, depending on the time and method of application. Significant reductions in the concentration of ammoniacal-N in floodwater resulted when PPD-amended urea was applied between 18 and 26 days after transplanting (DT). In contrast, PPD did not appreciably affect the concentration of ammoniacal-N in floodwater when applied with urea either immediately before or after transplanting of the seedlings.Plant N uptake and grain yield were not significantly affected by the addition of PPD with urea in three of the four experiments conducted, even though PPD substantially reduced the concentration of ammoniacal-N in the floodwater in several treatments in these studies. The¹⁵N balance studies conducted at both field locations showed PPD to increase total¹⁵N recovery by between 10% and 14% of the¹⁵N applied, 14 days after the application of urea. No further loss of¹⁵N occurred between the initial sampling (40 DT) and grain harvest at Los Baños. An increase in¹⁵N recovery occurred at grain harvest at Muñoz because¹⁵N-labeled urea was applied at 50 DT in the study. PPD increased the amount of¹⁵N in the plant and nonexchangeable soil N fraction at all harvests at Los Baños. In contrast, at Muñoz, PPD increased the quantity of¹⁵N in the KCL-extractable pool 14 days after urea was applied. Reasons for the discrepancies in results between experiments and the overall failure of PPD to increase grain yield are discussed.     

Cover Picture: Surface Wrinkles for Smart Adhesion (Adv. Mater. 4/2008)

A patterned adhesive, based on surface wrinkling through swelling of a laterally confined polymer film, is presented by Alfred J. Crosby and co‐workers on p. 711. The image highlights the interface between the wrinkles (bright cylinders) of the patterned adhesive separating from a glass substrate (circular region). Enhanced control of adhesion is attributed to contact line splitting, which is fundamental to adhesion control in numerous examples in nature, for example, the gecko.     

Use of high performance liquid chromatography for the identification and estimation of zearalenone, patulin and penicillic acid in food

A method is described for the estimation of 3 u.v.-absorbent mycotoxins in foods by using semi-preparative and analytical h.p.l.c. columns. The foodstuff is extracted using aqueous acetonitrile and fatty matter is removed from the extract by partition into 2,2,4-trimethylpentane. Mycotoxins present in the fat-free extract are then back extracted into chloroform and separated into two fractions on a silica gel column using (a) diethyl ether and (b) chloroform: methanol. Further purification on a semi-preparative alumina column is described prior to measurement of mycotoxin content on analytical h.p.l.c. columns. Recoveries of zearalenone, patulin and penicillic acid added at 2 to 4 times the detection limit to samples of meat, dairy products and cereals ranged from 50 to 100%.