Can memory requirements account for species' differences in invisible displacement tasks?

We tested the hypothesis that poor performance on the Piagetian invisible displacement task is related to increased memory requirements. Rhesus monkeys and orangutans received 3 types of problems (invisible, visible, and no transfer problems) each containing a number of steps equivalent to that of standard invisible displacements. If failure to solve invisible displacements was due to increased memory requirements, then the primates should perform at chance level on all 3 problems. However, rhesus monkeys solved visible and no transfer problems, but not invisible transfer problems. Half of the orangutans solved all 3 transfer problems, although their performance on invisible transfer problems was lower than that on the other problems. A subsequent cuing phase led to improved performance, and a few monkeys solved invisible transfer problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Understanding a link between sexual harassment and eating disorder symptoms: A mediational analysis.

Using data from 3 samples of working women and men, the present study examines the association between sexual harassment and eating disorder symptoms by studying the processes that may underlie this relationship. The results of structural equation modeling suggest a link between sexual harassment and eating disorder symptoms among women and indicate that this relationship is mediated by psychological distress, self-esteem, and self-blame. Further, sexual harassment was found to predict eating disorder symptoms among women even when experiences of sexual assault were included in the model. No relationship was found between sexual harassment and eating disorder symptoms among men. The theoretical and clinical implications of these results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Screening of phenylalanine ammonia lyase in plant tissues,and retention of activity during dehydration

BACKGROUND: Oral therapy with phenylalanine ammonia lyase (PAL), naturally encapsulated in plant cells, may provide a potential alternative treatment for hyperphenylalaninemic patients, including those with phenylketonuria. Therefore different sources of plant tissue were investigated for PAL activity. RESULTS: Enzyme activity was highest in grain seedlings, with maximal enzyme activity in 7‐day‐old red spring wheat (Triticum aestivum L.) seedlings. The PAL activities of leaves and roots/endosperm of wheat seedlings were 11.90 ± 2.64 and 6.48 ± 1.59 µmol h^?1 g^?1 dry weight respectively. Three PAL‐related polypeptides with molecular weights of 74, 83 and 103 kDa were identified in wheat seedling leaf tissues, while only the 74 kDa polypeptide was detected in root/endosperm tissues. Dehydration was investigated as a method of concentrating PAL in wheat seedlings. Freeze‐drying was found to retain the most PAL activity (>90% recovery on a dry weight basis) compared with air drying and vacuum microwave drying for both leaf and root/endosperm samples. CONCLUSION: This study has led to a better understanding of PAL activity and stability in plant tissues and provides the basis for developing a natural plant preparation as a dietary supplement for the treatment of hyperphenylalaninemia. Copyright © 2007 Society of Chemical Industry     

Assessing coparenting in families of school-age children: Validation of the Coparenting and Family Rating System.

Studied (1) the psychometric properties of an observational co-parenting measure and (2) the relationship between co-parenting and the adjustment of school-age children. Ss were 67 couples in the US with a 1st-born, 7-11 yr old child. Family interactions during unstructured family play in a laboratory setting were coded with the Coparenting and Family Rating System (CFRS; J. P. McHale et al, 2000). Three self-report measures of marital adjustment, the Child Behavior Checklist (CBCL), and the Revised Children's Manifest Anxiety Scale were administered. For boys, the CFRS measure Hostility-Competitiveness correlated with anxiety (Revised Children's Manifest Anxiety Scale) and with mother-reported internalizing, externalizing, and overall problems (CBCL). For girls, the CFRS measure Parenting Discrepancy correlated with mother-reported internalizing (CBCL). The possibility of sex differences in co-parenting-adjustment links is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ESMRMB 2017, 34th Annual Scientific Meeting,Barcelona, ES,October 19–October 21: Abstracts,Thursday

Objective

Current magnetic resonance imaging (MRI) axon diameter measurements rely on the pulsed gradient spin-echo sequence, which is unable to provide diffusion times short enough to measure small axon diameters. This study combines the AxCaliber axon diameter fitting method with data generated from Monte Carlo simulations of oscillating gradient spin-echo sequences (OGSE) to infer micron-sized axon diameters, in order to determine the feasibility of using MRI to infer smaller axon diameters in brain tissue.

Materials and methods

Monte Carlo computer simulation data were synthesized from tissue geometries of cylinders of different diameters using a range of gradient frequencies in the cosine OGSE sequence . Data were fitted to the AxCaliber method modified to allow the new pulse sequence. Intra- and extra-axonal water were studied separately and together.

Results

The simulations revealed the extra-axonal model to be problematic. Rather than change the model, we found that restricting the range of gradient frequencies such that the measured apparent diffusion coefficient was constant over that range resulted in more accurate fitted diameters. Thus a careful selection of frequency ranges is needed for the AxCaliber method to correctly model extra-axonal water, or adaptations to the method are needed. This restriction helped reduce the necessary gradient strengths for measurements that could be performed with parameters feasible for a Bruker BG6 gradient set. For these experiments, the simulations inferred diameters as small as 0.5 μm on square-packed and randomly packed cylinders. The accuracy of the inferred diameters was found to be dependent on the signal-to-noise ratio (SNR), with smaller diameters more affected by noise, although all diameter distributions were distinguishable from one another for all SNRs tested.

Conclusion

The results of this study indicate the feasibility of using MRI with OGSE on preclinical scanners to infer small axon diameters.

     

Quantitative detection of lactic acid bacteria in dried sourdoughs using real-time PCR

A real-time PCR system with 16S rRNA gene-targeted group-specific primers was developed to quantitatively detect lactic acid bacteria (LAB) of the genera Lactobacillus, Leuconostoc, Pediococcus, and Weissella in different types of commercially available dried sourdoughs. Despite a high degree of degradation in the DNA isolated from the doughs, the 341-bp 16S rRNA gene fragment of the sourdough LAB biota could specifically be amplified. For dried sourdoughs, the resulting calculated LAB cell counts were determined to be up to 3.7 × 10⁷ cells/g fresh dough, whereas in non-fermented dough acidifiers, used as a control, the calculated LAB cell counts did not exceed 3.6 × 10⁴ cells/g fresh dough. Moreover, the effect of low pH and/or high lactic acid concentrations prevailing in the doughs on the detectability of LAB cells in spray- and roller-dried sourdoughs by PCR was investigated. Drying of non-acidified sourdoughs still permitted to detect the LAB cells by PCR, whereas drying of acidified doughs reduced the detectable cell counts by approximately 5 (spray dried) and 2 (roller dried) orders of magnitudes. Incubation of acidified doughs for 24 h did not affect the detectability of LAB cells in spray-dried doughs but further reduced the detectable cell counts in roller-dried doughs by additional 2 orders of magnitude.     

Modeling improvements in booster seat use: a discrete choice conjoint experiment

Automobile crashes are the leading cause of death in children aged 1–14 years. Many children, however, are not properly restrained in safety seats that reduce serious injury and death. This study used a discrete choice conjoint experiment to study factors influencing the decision to use booster seats. Parents of 1714 children aged 4–9 years from nine Canadian provinces completed choice tasks presenting experimentally varied combinations of 15 4-level booster seat promotion attributes. Latent class analysis yielded three segments of parents. The choices of the Benefit Sensitive segment (50%) were most sensitive to the injury prevention benefits of booster seats. The choices of parents in the Context Sensitive segment (33.5%) were more likely to be influenced by installation complexity, oppositional behavior, and the prospect that their child may be teased for riding in booster seats. Parents in the High Risk segment (16.5%) were younger, less educated, and less knowledgeable about vehicle safety legislation. They anticipated fewer benefits, expected more barriers and were less likely to use booster seats. Simulations suggest that consistent enforcement coupled with advertising focusing on injury prevention and the use of booster seats by other parents would increase adoption.     

Approach for measuring the chemistry of individual particles in the size range critical for cloud formation

Aerosol particles, especially those ranging from 50 to 200 nm, strongly impact climate by serving as nuclei upon which water condenses and cloud droplets form. However, the small number of analytical methods capable of measuring the composition of particles in this size range, particularly at the individual particle level, has limited our knowledge of cloud condensation nuclei (CCN) composition and hence our understanding of aerosols effect on climate. To obtain more insight into particles in this size range, we developed a method which couples a growth tube (GT) to an ultrafine aerosol time-of-flight mass spectrometer (UF-ATOFMS), a combination that allows in situ measurements of the composition of individual particles as small as 38 nm. The growth tube uses water to grow particles to larger sizes so they can be optically detected by the UF-ATOFMS, extending the size range to below 100 nm with no discernible changes in particle composition. To gain further insight into the temporal variability of aerosol chemistry and sources, the GT-UF-ATOFMS was used for online continuous measurements over a period of 3 days.