Electrospray-atmospheric sampling glow discharge ionization source for the direct analysis of liquid samples

Coupling electrospray with atmospheric sampling glow discharge ionization for the direct analysis of liquid-phase samples is demonstrated. Electrospray is utilized for nebulizing and transporting intact sample molecules into the glow discharge where ionization occurs through various pathways, including electron ionization and ion-molecule reactions with reagent ions. Reagent ions are formed through ionization of air molecules in an area of reduced pressure. The effects of discharge current, electrospray voltage, and solution flow rate on the absolute and relative ion intensities observed in the mass spectra are discussed. This technique is applicable to compounds containing various functional groups and encompassing a range of volatility. Analysis of organic compounds with varying volatility and polarity is discussed to illustrate the utility of this ionization technique.     

Rasch analysis of inattentive, hyperactive and impulsive behaviour in young children and the link with academic achievement

The Attention Deficit Hyperactivity Disorder (ADHD) criteria from the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders were used to assess a large sample of children at the end of their first year at school in England. These data were explored using Rasch measurement and the measures for the items together with their frequencies are reported. The data were further analysed in three ways: a) The results were compared with a previous similar analysis of college students. b) A principal components analysis of the item residuals from the Rasch analysis was conducted. c) The measures were linked to reading and mathematics attainment assessed at three different time points. The exploration supported previous work and theoretical positions, and in doing so raised issues about the appropriateness of the use of the criteria across all ages. It also suggested that one of the currently recognised ADHD sub-types could be further sub-divided into verbal and physical hyperactivity. The links to academic achievement raised questions about the integrity of the currently recognised ADHD sub-types and the paper calls for further investigations.     

An ergonomic intervention to reduce back strain among apple harvest workers in New York State

The impact of modifications to the apple picking bucket on common picking postures, self-reported comfort, ease of use, and speed of harvest were measured. Fourteen apple pickers wore an intervention hip belt, were interviewed and measured using posture-activities-tools-handling methodology. The use of hip belt did not significantly alter time spent in various postures. 78.6% of interviewed workers preferred the modified bag, 71.4% noted a difference in the back, neck, or shoulder, while 64.3% said regular use of modified bag would slow their work. Major themes in worker comments are discussed. The hip belt modification to apple harvest bag seems generally acceptable to workers, but needs further development to overcome unintended effects. Although work sampling demonstrates that the bag does not affect work practices, workers appear somewhat concerned that productivity will be negatively impacted. Further training of workers in the use and potential benefits of bag are needed.     

Sources of Chemical Signals which Enhance Multiparasitism Preference by a Cleptoparasitoid

The cleptoparasitoid Eupelmus vuilleti recognizes and prefers laying on hosts parasitized by Dinarmus basalis to unparasitized hosts. This recognition is based on the perception of a chemical substance deposited on the surface of the seed. Dufour’s gland secretion and cuticular hydrocarbons of D. basalis are attractive and may mediate the host discrimination. This activity is linked to a mixture of linear and methyl alkanes whose source is apparently the Dufour’s gland.     

Changes in the nutritional composition of two varieties of orchard pear buds during the period of maximum bird damage

Damage to fruit buds by bullfinches (Pyrrhula pyrrhula L.) is a serious problem to the fruit-growing industry in the UK. The nutrient composition of two varieties of pear buds, ‘Conference’ and ‘Doyenne du Comice’ has been determined at intervals between mid-February and April 1981, the time of maximum bird damage. Bullfinches preferentially take buds from Conference pear trees while Doyenne du Comice is a less favoured variety. The chemical differences between these two varieties have been shown to be slight with reference to the total nitrogen, free amino acid, protein hydrolysate amino acid, glyceride glycerol, glucose, fructose, sucrose, starch, phosphorus and cation contents. Thus the basis of the birds' preference may lie in the individual components of the groups of nutrients studied, secondary metabolites and/or the physical/developmental differences between bud varieties.     

Influence of control of shock on subsequent shock-elicited aggression.

Shocks which cannot be controlled by an organism have been shown to interfere with subsequent escape-avoidance training more than do equivalent shocks which can be controlled. 2 experiments extended the generality of this phenomenon by examining the effects of the escapability of shock on subsequent shock-elicited aggression. Exp. I (with 48 male Sprague-Dawley rats) found that prior exposure to inescapable shock reduced the frequency of shock-induced fighting, while escapable shock did not produce such a reduction. The theory that yoked-control procedures can capitalize on individual differences and produce a systematic difference between groups was ruled out as an explanation of the data of Exp. I by the results of Exp. II, conducted with 22 similar Ss. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contingency Management of Reliable Attendance of Chronically Unemployed Substance Abusers in a Therapeutic Workplace.

The Therapeutic Workplace is an effective drug abuse treatment that integrates abstinence reinforcement into a work setting by using a salary that drug abusers earn for work. Drug abuse patients are trained and hired to become data entry operators in a Therapeutic Workplace business. Despite the opportunity to earn a high wage, participants frequently arrive at work late and fail to work complete shifts. In the present study, a contingency management intervention to promote consistent and reliable attendance was evaluated in 4 participants. Participants were not allowed to work on days that they arrived late, and their pay was temporarily reduced each time they arrived late at work or failed to complete a work shift. A within-subject reversal design showed that the intervention increased the frequency with which participants arrived at work on time and completed work shifts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

照度传感器改善移动设备的电源管理

在手机和其他移动电子设备中,随着彩色液晶显示(LCD)以及其它功耗很大的附加功能(如摄像头、全球定位系统等)应用不断普及,功耗问题变得越来越关键。设计者现在采用的改进功耗管理的办法之一,是利用输出响应与人眼功能类似的照度传感器来检测环境光亮度。在使用照度传感器的情况下,移动设备可以根据环境光照条件关闭或调整键盘/LCD的背光。这样就可以有效的降低功耗、延长电池寿命。照度传感器的各种关键应用照度传感器的应用包括:亮度调节:照度传感器的测量结果可以用来调节显示器的亮度,或者优化背光照明,使之与环境光条件协调一致,从…     

Cross-stressor immunization against the behavioral deficits introduced by uncontrollable shock.

In 4 experiments with 204 male CD-1 mice, exposure to inescapable shock disrupted performance in both shock- (SE) and water-escape (WE) tasks. These deficits were prevented in Ss that were previously trained in the same task. However, an asymmetrical immunization effect was seen in a cross-stressor paradigm. Whereas deficits of WE performance engendered by inescapable shock were prevented by prior SE training, the deficits of SE were not eliminated by prior WE training. Evidently, the immunization effect occurs when initial training and subsequent testing are conducted in the same task or when the initial training and uncontrollable stress session involve the same aversive stimulus. Norepinephrine (NE) determinations revealed that reductions of NE introduced by inescapable shock were unaffected by prior SE training and were enhanced by prior exposure to the stress of water immersion. Thus, although the performance deficit introduced by inescapable shock may be related to variations of NE, the immunization effect probably was unrelated to alterations of NE. Data provisionally suggest that the immunization stems from 2 independent factors: Initially training Ss in an active escape task may (a) disrupt subsequent learning that the inescapable stress actually is uncontrollable and (b) limit the influence of the motor deficits introduced by uncontrollable shock on subsequent escape performance. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)