Early detection of fungal biomass on library materials

Library materials are susceptible to fungal deterioration. The paper constituents of archival materials are subjected to harmful physical and chemical processes as they are slowly consumed by fungi. Remediation of fungal contamination can be costly and risk further damage to fragile or previously degraded materials. Early detection of fungal growth would permit the use of relatively noninvasive treatments to remediate fungal contamination of artifacts before visible or lasting damage has occurred. Current methods used for the detection of microbial biomass, such as colony counts, microscopic biovolume estimation, and ergosterol analysis are expensive, time consuming, or are inappropriate for use with fungi. Beta-N-acetylhexosaminidase (EC 3.2.1.52) activity provides a rapid and reliable means of fungal detection on a variety of cultural heritage materials. Adapted for use on archival materials, fluorogenic 4-Methylumbelliferyl (MUF) labeled substrate N-acetyl-Beta-D-glucosamine (NAG) was used to detect fungal beta-N-acetylhexosaminidase activity. The fluorescence generated by minute quantities of fungi was quickly detected at an early stage of growth. The sensitivity of the assay was comparable to other biochemical techniques. The fluorometric assay was well-suited for early detection of fungal biomass on paper and assessment of the effectiveness of common remediation practices.     

The Development of Study Orientations and Study Success in Students of Pharmacy

In research literature, two study orientations have been identified: meaning orientation and reproducing orientation. Few studies have examined how study orientations and conceptions of knowledge (epistemologies) interrelate. Further, longitudinal studies of the development of orientations and of conceptions of knowledge in relation to academic achievement are scarce. The study set out:(i) to examine the relationship between study orientations and conceptions of knowledge; (ii) to investigate how these kinds of beliefs change during short, career-aimed studies of natural science; (iii) to explore how study orientations and changes in them are related to study success. The sample consisted of 66 undergraduate students of pharmacy studying at a Finnish university. Participants filled in a questionnaire regarding study orientations and conceptions of knowledge at the beginning of their studies and after 3 years of study. Results showed a relationship between reproducing orientation and dualist conceptions of knowledge. Reproducing orientation and dualism diminished during undergraduate natural science studies. Further, students' reproducing orientation after the last study year was negatively related to their study success. In addition, a favourable development was detected in the group of above-average achievers, who maintained their initial level of meaning orientation while diminishing their level of reproducing orientation. Implications for instruction are discussed.     

Independent component analysis via optimum combining of kurtosis and skewness-based criteria

This paper introduces blind separation methods that are based on minimization of mutual information. Direct minimization of mutual information leads to estimating functions that change on every iteration of separating algorithm unlike in the maximum likelihood approach employing fixed non-linearity. We propose objective functions for source separation that are comprised of a symmetric and an asymmetric part. This allows for separating signals that may have skewed distributions. The optimal weighting between the symmetric and the asymmetric part is determined from the data based on an efficacy measure. The performance of the proposed objective functions is studied in cases where some source signals may be asymmetrically distributed. The capability of adapting to different type of source distributions is demonstrated in simulations.     

Differences in Self-Regulation for Online Learning Between First- and Second-Generation College Students

Self-regulation is generally accepted as an important construct in student success within environments that allow learner choice, such as online courses. The purpose of the current study was to investigate differences between first- and second-generation college students' ability to self-regulate their online learning. An ANCOVA, with comfort level using the computer as a control, provided evidence that first-generation students report significantly lower levels of self-regulation for online learning than their second-generation counterparts.     

The impact of adverse childhood experiences on an urban pediatric population

Objective

The goal of this study was to investigate the adverse childhood experiences (ACEs) in youth in a low-income, urban community.

Study design

Data from a retrospective chart review of 701 subjects from the Bayview Child Health Center in San Francisco are presented. Medical chart documentation of ACEs as defined in previous studies were coded and each ACE criterion endorsed by a traumatic event received a score of 1 (range = 0-9). This study reports on the prevalence of various ACE categories in this population, as well as the association between ACE score and two pediatric problems: learning/behavior problems and body mass index (BMI) ≥ 85% (i.e., overweight or obese).

Results

The majority of subjects (67.2%, N = 471) had experienced 1 or more categories of adverse childhood experiences (ACE ≥ 1) and 12.0% (N = 84) had experienced 4 or more ACEs (ACE ≥ 4). Increased ACE scores correlated with increased risk of learning/behavior problems and obesity.

Conclusions

There was a significant prevalence of endorsed ACE categories in this urban population. Exposure to 4 or greater ACE categories was associated with increased risk for learning/behavior problems, as well as obesity.

Practice implications

Results from this study demonstrate the need both for screening of ACEs among youth in urban areas and for developing effective primary prevention and intervention models.