Temporal shifts in the biodiversity of nearshore small fishes in Lake Simcoe

Nearshore small fish species represent a large proportion of fish biodiversity in Lake Simcoe, a large inland lake in southern Ontario, Canada. Over the past 30 years, Lake Simcoe has experienced several changes to its aquatic habitat, benthic invertebrate communities and predatory fish populations. This study compared samples of the nearshore small fish community in three geographic areas of Lake Simcoe. Fish community data were grouped into two time periods: a contemporary period (2007–2009) and a historical period (1982–1995). The fish community was compared across time periods for each area to assess if observed ecological changes had an impact on the small fish community. Species richness significantly declined between time periods in two areas (Cook's Bay and the southeast shoreline), the number of individuals captured declined between time periods in one area of the lake (Kempenfelt Bay) and Simpson's diversity index declined between time periods in one area of the lake (southeast shoreline). There were no significant differences in the Shannon–Weiner evenness index between time periods in any of the study areas. Additional analyses of intra- and inter-annual variation in fish sampling results generally supported the findings that shifts in the fish community occurred between time periods. Overall, this study suggests that the nearshore small fish biodiversity of Lake Simcoe has shifted over time but these shifts are not clearly related to recent increases in water clarity, macrophyte growth and nearshore benthic invertebrate densities.     

Academic effectiveness of podcasting: A comparative study of integrated versus supplemental use of podcasting in second language classes

With podcasting gaining more mainstream adoption in higher education, it’s critical to examine its effectiveness in improving the student learning experience. To this end, this paper examines the effectiveness of podcasts integrated into the curriculum (PIC) versus podcasts as supplemental material (PSM). Considering recent empirical work on the effectiveness of podcasting, this study collected data from students enrolled in lower level and upper level language courses. Results revealed an inconclusive relationship among PIC students’ learning outcomes (as measured by their final grades). In contrast, however, our findings indicate a strong relationship between the use of PSM and students’ final grades, particularly in upper level courses.     

Determination of density distribution in ferrous powder compacts using ultrasonic tomography.

Laser-induced ultrasonic bulk wave tomography is used for density variation determination of powder metal compacts. A laser beam is used to excite ultrasonic energy, and the signals passing through the specimen are received by an air-coupled transducer. The density variations of powder metal compacts can be determined directly by the cross-sectional tomographic images of slowness obtained by using a filtered, backprojection algorithm based on measured time of flights. Interpolations with respect to sample and projection angles are used to generate the input data required for displaying a well-balanced, reconstructed image to reduce the aliasing distortions caused by insufficient input data. Results of presintered cylindrical ferrous powdered samples show that this novel approach makes the reconstruction process more cost effective than the very tedious, time-consuming, and inaccurate metallographic methods, thus making it a potentially powerful tool for studying manufacturing processes through significant parameters to obtain a more uniform density distribution.     

Classifying and detecting anomalies in hybrid knowledge-based systems

The increasing need for hybrid Knowledge-Based Systems (KBS) that accommodate more complex applications has led to the need for new verification concerns that are more specific to the hybrid representation using objects and rule-based inference. Traditionally, verification of expert systems has focused solely on rule-based inference systems. Hybrid KBSs present additional verification problems not found in traditional rule-based systems. This paper is an investigation into the anomalies that may be present in a hybrid representation that warrant detection for the verification of the KBS. Many anomalies are due to the interaction of the component parts of the hybrid KBS. For example, subsumption anomalies arise due to an interaction between inheritance of objects and rule-based inference. In this paper, we extend the context of subsumption anomalies and introduce additional types of anomalies that may be present in the KBS. The goal of this research is to make hybrid KBSs more reliable by detecting such anomalies.     

Overt and Relational Aggression and Perceived Popularity: Developmental Differences in Concurrent and Prospective Relations.

Relations of overt and relational aggression with perceived popularity among children and early adolescents were examined in 2 studies (Ns = 607 and 1,049). Among older youths, positive concurrent relations found between overt aggression and perceived popularity became nonsignificant when relational aggression was controlled, whereas positive associations found between relational aggression and perceived popularity held when overt aggression was controlled. Aggression and perceived popularity were not positively related for the younger participants. The 2nd study also examined the temporal ordering of these relations over 6 months. For older girls, positive relations between relational aggression and perceived popularity were bidirectional. For older boys, relational aggression did not predict increased perceived popularity, but perceived popularity predicted increased relational aggression. Implications for intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Knowing and Not Knowing About Trauma: Implications for Therapy.

Levels of awareness for trauma and their consequences for research, treatment, and prevention within professional psychology and society are considered. When people must endure chronically traumatic environments, it may be adaptive to isolate from awareness information that would produce cognitive dissonance and threaten necessary relationships. Unawareness may also facilitate functioning in environments that invalidate the prevalence and impact of trauma. In addition, characteristics of the posttraumatic environment can promote or impede individuals' awareness of trauma and their psychological functioning. Though often initially adaptive, unawareness for trauma is linked to intergenerational transmission of trauma and its effects and may preclude public and professional attention to trauma treatment and prevention. Understanding the processes through which individuals become unaware or aware of traumatic experience is therefore essential to conducting effective psychotherapy with trauma survivors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluation of four blood pump geometries: the optical tracer technique

Artificial blood pump assistance of the failing human heart can allow it to recover. Analysis of blood pump fluid flow is a useful tool for design development and thrombosis minimization. The aim of this study was to investigate fluid flow, particularly ventricular clearance rate and stagnation areas, in four different blood pump geometries and to determine the best design. The blood pumps consisted of a polyurethane ventricle, and combinations of inlet/outlet pipe angles and compression plate shapes. A video camera recorded the motion of fluid labelled with an optical tracer (Methyl Blue histological dye). A novel processing method was developed to produce colour maps of tracer concentration, experimentally calibrated. An overall picture of fluid flow in each pump geometry was generated by considering clearance curves, tracer concentration maps and inflow jet animations. Overall and local mixing coefficients are calculated for each pump. The best geometry featured straight inlet/outlet pipes and a domed compression plate. This optical tracer technique has proven convenient, economical, sensitive to low concentrations of tracer and provides instantaneous pictures of tracer distribution in a ventricle.     

Access to Pediatric Neurologists - Will Telemedicine Close the Gap?

Many times both physicians and patients take for granted that they are qualified to treat certain ages and certain conditions. Neurological conditions are diagnosed and treated by neurologists, pediatric neurologists, and neurosurgeons. What is the difference and why does it matter? It is a balancing act of risk and benefit and the physician’s obligation to know her/his limitations. Telemedicine may play a key role in enabling a greater access to pediatric neurologists. If telemedicine becomes more available, then access even in more remote areas without child neurologists may be possible. As this article discusses, there may be certain limitations to using telemedicine, which is distinguishable from telehealth, in relation to pediatric neurology. This article examines the type of neurological physician that is the most appropriate; the availability of and access to pediatric neurologists; and the applicability of telemedicine to the diagnosis and treatment of pediatric neurological conditions.