Enzymatic detoxification strategies for neurotoxic insecticides in adults of three tortricid pests.

We examined the role of the most important metabolic enzyme families in the detoxification of neurotoxic insecticides on adult males and females from susceptible populations of Cydia pomonella (L.), Grapholita molesta (Busck), and Lobesia botrana (Denis & Schiffermüller). The interaction between the enzyme families - carboxylesterases (EST), glutathione-S-transferases (GST), and polysubstrate monooxygenases (PSMO) - with the insecticides - chlorpyrifos, λ-cyhalothrin, and thiacloprid - was studied. Insect mortality arising from the insecticides, with the application of enzyme inhibitors - S,S,S-tributyl phosphorotrithioate (DEF), diethyl maleate (DEM), and piperonyl butoxide (PBO) - was first determined. The inhibitors' influence on EST, GST, and PSMO activity was quantified. EST and PSMO (the phase-I enzymatic activities) were involved in the insecticide detoxification in the three species for both sexes, highlighting the role of EST, whereas GST (phase-II enzymes) was involved only in G. molesta insecticide detoxification. L. botrana exhibited, in general, the highest level of enzymatic activity, with a significantly higher EST activity compared with the other species. It was the only species with differences in the response between sexes, with higher GST and PSMO activity in females than in males, which can be explained as the lower susceptibility of the females to the tested insecticides. A positive correlation between PSMO activity and the thiacloprid LD50s in the different species-sex groups was observed explaining the species-specific differences in susceptibility to the product reported in a previous study.

Direct Aggression and the Balance between Status and Affection Goals in Adolescence.

Previous studies have shown that status goals motivate direct forms of interpersonal aggression. However, status goals have been studied mostly in isolation from affection goals. It is theorized that the means by which status and affection goals are satisfied change during adolescence, which can affect aggression. This is tested in a pooled sample of (pre)adolescents (N = 1536; 49% girls; ages 10-15), by examining associations between status goals and direct aggression and the moderating role of affection goals. As hypothesized, with increasing age, status goals were more strongly associated with direct aggression. Moreover, for older adolescents, status goals were only associated with aggression when affection goals were weak. These findings support the changing relationship between status goals and direct aggression during adolescence.

Chasing quantitative biases in neutron imaging with scintillator-camera detectors: a practical method with black body grids.

We propose a method for improving the quantification of neutron imaging measurements with scintillator-camera based detectors by correcting for systematic biases introduced by scattered neutrons and other sources such as light reflections in the detector system. This method is fully experimental, using reference measurements with a grid of small black bodies (BB) to measure the bias contributions directly. Using two test samples, one made of lead alloy and having a moderate (20%) neutron transmission and one made of stainless-steel and having a very low (1%) transmission, we evaluated the improvement brought by this method in reducing both the average quantification bias and the uncertainty around this average bias after tomographic reconstruction. The results show that a reduction of the quantification bias of up to one order of magnitude can be obtained. For moderately transparent samples, little sensitivity is observed to the parameters used for the correction. For the more challenging sample with very low transmission, a correct placement of the BB grid is of utmost importance for a successful correction.

The Interplay Between Status and Affection Needs: Testing the Imbalanced Needs Theory of Aggression in Adulthood.

Status and affection are both goals related to social needs. The imbalanced needs theory of aggression proposes that although aggression can be used to realize status, this strategy is detrimental for realizing affection in the same social context. Thus, to the degree that the social circles overlap in which status and affection needs are realized, it becomes more costly (in terms of affection) to achieve status via aggression. This theory was tested for different forms of aggression, in different contexts, in a sample of adults from the general population (N = 253, M age = 29.95, SD = 2.60, 78% female). Participants reported on social needs with the Interpersonal Goals Inventory and reported on general measures of physical and social aggression, as well as rule breaking, and aggression at the workplace and in intimate partner relationships. As hypothesized, status needs were associated with physical aggression when affection needs were weak. This interaction, though to a lesser degree, also extended to social forms of aggression and rule breaking. At the workplace, aggression was only related to weak affection needs, whereas aggression in intimate partner relationships was, as expected, unrelated to both social needs. Together, these findings support the results of an earlier test of the imbalanced needs theory of aggression in adolescence, and encourage more research into the link between aggression and the satisfaction of social needs.

Tools for resistance monitoring in oriental fruit moth (Lepidoptera: Tortricidae) and first assessment in Brazilian populations.

In southern Brazilian apple (Malus spp.) orchards, predominantly organophosphates are used to control the oriental fruit moth, Cydia molesta (Busck) (Lepidoptera: Tortricidae), but control failures often occur. Therefore the susceptibility of three C. molesta Brazilian populations was investigated to five insecticides of different groups and modes of action, in comparison with a susceptible laboratory strain mass reared in southern France for >10 yr. At the same time, comparative biochemical and genetic analysis were performed, assessing the activities of the detoxification enzymatic systems and sequencing a gene of insecticide molecular target to find out markers associated with resistance. The three Brazilian populations were significantly resistant to chlorpyrifos ethyl compared with the reference strain. One of the field populations that had been frequently exposed to deltamethrin treatments showed significant decreasing susceptibility to this compound, whereas none of the three populations had loss of susceptibility to tebufenozide and thiacloprid compared with the reference strain. All three populations had slight but significant increases of glutathione transferase and carboxylesterases activities and significant decrease of specific acetylcholinesterase activities compared with the reference. Only the most resistant population to chlorpyriphos exhibited a significantly higher mixed function oxidase activity than the reference. The acetylcholinesterase of females was significantly less inhibited by carbaryl in the Brazilian populations than in the reference strain (1.7-2.5-fold), and this difference was not expressed in the male moth. However, no mutation in the MACE locus was detected. These biological and molecular characterizations of adaptive response to insecticides in C. molesta provide tools for early detection of insecticide resistance in field populations of this pest.

Being there with others: how people make environments norm-relevant.

In two studies we show that people make environments norm-relevant and this increases the likelihood that environments influence norm-relevant judgments. When people see environments without having people on their mind, this effect does not occur. Specifically, when exposed to an environment (a library), people's perceived importance of environment-relevant norms (be silent in libraries) increases, when the concept of 'people' is primed compared to when this is not the case. The impact on normative judgments of priming significant others (Study 1) is stronger than priming people in general (Study 2). Additional effects on conformism and public self-consciousness are discussed, as well as implications for future studies.

Silence and table manners: when environments activate norms.

Two studies tested the conditions under which an environment (e.g., library, restaurant) raises the relevance of environment-specific social norms (e.g., being quiet, using table manners). As hypothesized, the relevance of such norms is raised when environments are goal relevant ("I am going there later") and when they are humanized with people or the remnants of their presence (e.g., a glass of wine on a table). Two studies show that goal-relevant environments and humanized environments raise the perceived importance of norms (Study 1) and the intention to conform to norms (Study 2). Interestingly, in both studies, these effects reach beyond norms related to the environments used in the studies.

A Monte Carlo approach for scattering correction towards quantitative neutron imaging of polycrystals.

The development of neutron imaging from a qualitative inspection tool towards a quantitative technique in materials science has increased the requirements for accuracy significantly. Quantifying the thickness or the density of polycrystalline samples with high accuracy using neutron imaging has two main problems: (i) the scattering from the sample creates artefacts on the image and (ii) there is a lack of specific reference attenuation coefficients. This work presents experimental and simulation results to explain and approach these problems. Firstly, a series of neutron radiography and tomography experiments of iron, copper and vanadium are performed and serve as a reference. These materials were selected because they attenuate neutrons mainly through coherent (Fe and Cu) and incoherent (V) scattering. Secondly, an ad hoc Monte Carlo model was developed, based on beamline, sample and detector parameters, in order to simulate experiments, understand the physics involved and interpret the experimental data. The model, developed in the McStas framework, uses a priori information about the sample geometry and crystalline structure, as well as beamline settings, such as spectrum, geometry and detector type. The validity of the simulations is then verified with experimental results for the two problems that motivated this work: (i) the scattering distribution in transmission imaging and (ii) the calculated attenuation coefficients.

Do they get what they want or are they stuck with what they can get? Testing homophily against default selection for friendships of highly aggressive boys. The TRAILS study.

In this study a homophily selection hypothesis was tested against a default selection hypothesis, to answer whether preferred and realized friendships of highly aggressive boys differed. In a large peer-nomination sample, we assessed who highly overt aggressive, low prosocial boys (n = 181) nominated as friends (preferred friendships) and who among the nominated friends reciprocated the friendship (realized friendships). These preferred and realized friendships were compared with those of less aggressive (n = 1,268) and highly aggressive but also prosocial boys (bi-strategics; n = 55). Results showed that less aggressive boys preferred peers low on aggression, whereas highly aggressive and bi-strategic boys preferred peers not particular high or low on aggression. In line with default selection, highly aggressive boys ended up with aggressive peers even though that was not their preference. In general, received support proved an important determinant of highly aggressive, bi-strategic, and less aggressive boys' preferred and realized friendships. Especially highly aggressive boys preferred emotionally supportive friends, but ended up with the least supportive peers. In sum, for friendships of highly overt aggressive boys, the evidence favors default selection over homophily selection.

Orientation towards living in an old age home: an instrument to predict use of an old age home.

BACKGROUND: This study presents an alternative assessment method for establishing the demand for an old age home among a community-dwelling older population. The instrument, called 'orientation towards admission into an old age home', represents the intensity of the need for admission as expressed by older people themselves. Therefore it is indicative of the 'subjective demand'. METHODS: Using a longitudinal design (1993-98), the study tests whether a stronger orientation towards admission into an old age home leads to use of an old age home. This assessment method is compared with another method of assessing 'subjective demand', that is by those who have applied for and are waiting for admission. Additionally, the method is compared with an 'objective' indicator of demand, that is, the level of physical impairments and age of the elderly person. RESULTS: Results show that the subjective demand as measured by the 'orientation toward admission into an old age home' is indeed related to actual use of an old age home. The subjective demand as measured by being on a waiting list is not significantly related to the use of an old age home. The level of physical impairments (the objective demand) and age are sometimes, but not always, significantly related to the use of an old age home. CONCLUSION: The instrument 'orientation' provides us with a valuable instrument in assessing 'subjective demand' for an old age home among community-dwelling older people.