Cadmium-binding protein components of flaxseed: Influence of cultivar and location

The distribution of cadmium-(Cd)-binding components from five flaxseed cultivars grown at three locations in southern Manitoba was investigated to examine genotypic and environmental effects. Three protein fractions with different electrostatic properties, eluting at 0.10, 0.25 and 0.50 M NaCl by ion-exchange chromatography DEAE-Sephacel, represented 12%, 66% and 7% of the bound (extracted) protein, respectively, while 15% of the protein remained unbound. Cadmium and other divalent metal (zinc, copper and calcium) contents of protein fractions were strongly influenced by location. Cultivar differences in protein and cadmium contents of the protein fractions were highly significant. Cadmium and zinc accumulated similarly in the 0.10 and 0.25 M protein fractions at 51% and 40–43%, respectively. Transfer of copper occurred prominently in the 0.50 M fraction while most of the calcium (55%) remained unbound. The distribution of cadmium, zinc, copper and calcium in fractions of flaxseed proteins was strongly influenced by cultivar and location, indicating differences in their accumulation, migration and transfer.     

Peer Reviewed: An Economic Perspective on Outdoor Residential Pesticide Use

Pesticides.     

Electrical properties of polymer composites prepared by sintering a mixture of carbon black and ultra-high molecular weight polyethylene powder

Conductive polymer composites were prepared by sintering a mixture of ultrahigh molecular weight polyethylene (UHMWPE) powder and carbon black. Two processing parameters—time and temperature—were shown to have a notable effect on the resistivity of the composites. The relationships between the processing parameters and morphology were studied using optical microscopy and transmission electron microscopy (TEM). The results of the optical microscopy studies indicate that the carbon black is distributed in the interfacial regions between the UHMWPE particles. The dimension of the carbon black channels increases with the carbon black concentration. TEM micrographs show that a high degree of intermixing between the carbon black and the polymer occurs at higher temperatures and longer processing times, resulting in higher resistivities. A positive temperature coefficient (PTC) effect was observed for these materials. A mechanism for the PTC effect in this system is proposed. The magnitude of the PTC effect is found to be inversely proportional to the dimension of the carbon black channels in the composites. The dimension is directly related to the carbon black concentration. The PTC effect is a result of the polymer volume expansion caused by melting of the crystallites. A large PTC effect is observed for the composites with a low carbon black concentration and vice versa. No negative temperature effect (NTC) is observed at temperatures substantially above the melting point of the polymer.     

The effects of manual-based training on treatment fidelity and outcome: A review of the literature on adult individual psychotherapy.

The authors examine training issues related to the use of treatment manuals in psychotherapy outcome research. In particular, they examine methodological considerations such as the operationalization of manual-based training, trainer effects, therapist variables that mediate training, issues related to experimental design, and the choice and definition of appropriate dependent variables. The research literature indicates that manual-based training can produce technical adherence. Improvements in treatment competence were seen within, as opposed to across, cases. Researchers have been unable to draw strong links between treatment fidelity and patient outcomes. The review concludes that the limited focus on training studies in the manual-based treatment field compromises conclusions drawn from psychotherapy outcome research that relies on manuals to ensure a uniform delivery of the experimental variable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological functioning among mothers of children with insulin-dependent diabetes mellitus: A longitudinal study.

Mothers of children with newly diagnosed insulin-dependent diabetes mellitus (IDDM) were assessed repeatedly over a period of 6 years in order to determine the psychological correlates of managing this chronic illness. Both maternal depression and overall emotional distress after the 1st year of the IDDM increased slightly with illness duration and were also influenced by other factors. Mothers' adjustment shortly after their children were diagnosed with IDDM was a strong predictor of their long-term emotional symptomatology. However, mothers' symptoms over time were not related to medical aspects of IDDM (i.e., the extent of the children's metabolic control, number of rehospitalizations, or their compliance with the medical regimen) and were also unrelated to the levels of depression or anxiety reported by their children. Mothers generally found it easier to cope with the IDDM the longer their children had the illness. However, the degree to which mothers perceived the IDDM to be bothersome or difficult to manage at any given point in time was associated with their overall levels of emotional distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genomics of industrial Aspergilli and comparison with toxigenic relatives

Aspergillus oryzae has been used in Japanese fermentation industries for more than a thousand years. The species produces large amounts of various hydrolytic enzymes and has been successfully applied to modern biotechnology. The size of the A. oryzae genome (37.5 Mb) is very close to that of A. flavus and A. niger, and 20-30% larger than that of either A. nidulans or A. fumigatus. A. oryzae and A. flavus have exactly the same number of aspartic proteinase genes, of which each orthologous pair shares highly conserved amino acid sequences. Synteny analysis with A. fumigatus and A. nidulans showed that the A. oryzae genome has a mosaic structure consisting of syntenic and non-syntenic blocks. In the microorganisms to be compared, the density of the genes having homologs was obviously higher on the syntenic than on the non-syntenic blocks. Expression analysis by the DNA microarray supported the significantly lower expression of genes on the non-syntenic than on the syntenic blocks.     

Wetting and spreading of molten aluminium against AlN surfaces

Wetting and spreading of molten aluminium against AlN substrates were investigated between 1100 and 1290°C. The contact angles decreased linearly with time under isothermal conditions between 1100 and 1200°C. The isothermal rate of spreading of molten aluminium against AlN substrates was constant between 1220 and 1290°C and the rate increased exponentially with increasing temperature. Crystals of Al4C3 nucleated and grew on the substrate surface beneath the liquid. However, the formation of Al4C3 may not be solely responsible for the changes in contact angle and spreading. It is postulated that carbon contamination from the substrate and/or experimental equipment coupled with the low oxygen partial pressure of the chamber in the presence of graphite, were primarily responsible for the observed contact angle and spreading phenomena. The activation energy for the spreading process was 448 kJ mol-1, suggesting the presence of some chemical reaction at the interface. Carbon-rich aluminium may be initiating a continuous surface reaction with the AlN substrates by reducing the native oxide layer on the substrate surface.     

Clients, roles, and functions of the school psychologist.

The basic credo held by American school psychologists is that of child advocacy. Yet, with most school psychologists being employed by local school systems—where administrators often place institutional needs over individual student needs—the practitioner role is usually conflict-laden. Even though the preferred practitioner role is generally direct service to children through counseling or indirect student help via teacher consultation or parent counseling, at this time the school practitioner's major role in many settings is that of "gate keeping," which involves testing and certifying pupil eligibility for special education. If we look forward to the time when inappropriate gatekeeping—that is, formally labeling the mildly handicapped as eligible for special education—is eliminated, other functions performed must be strengthened and made more desirable to make the role of the school psychologist more viable. In addition to competent counseling skills, the ability to provide effective teacher consultation within schools is essential, not only for dealing with behavior, but instruction as well. The upgrading of school psychologists' skills is essential to ensure that, regardless of possible conflicts engendered, there will be at least one highly skilled child advocate working in the schools. (PsycINFO Database Record (c) 2010 APA, all rights reserved)