Through the Looking Glass: Examining the Practice of Science Classroom Dissection with a Multi-faceted Lens

Dissection of lab specimens is a common procedure in science classrooms, yet there are many unasked and unexamined questions relating to this practice. In addition to ethical considerations, there are personal and environmental health impacts of using conventional dissection, which has historically included animals and animal organs embalmed in preservative chemicals. The efficacy of using dissection as a learning tool is worth examining. The purpose of this thesis is to ask, analyze, and examine the multi-faceted questions associated with the use of dissection in the general science classroom. In addition, it is an invitation to engage a discussion about the possible negative consequences of using dissection, and to encourage consideration of alternatives that might be more ethically, pedagogically, and environmentally sound than existing practices. A review of the literature reveals that as many as 75% of classroom biology teachers use dissection and, generally, it is widely accepted and lauded as an important tool for learning about anatomy and physiology. Teachers express concern for a variety of issues associated with dissection, primarily student health and safety, and respect for lab specimens. As a response to these and other concerns, alternatives to physical dissection have been developed. These, however, are not widely used for a variety of reasons. The field research completed in this study is a qualitative analysis of the intellectual and emotional attitudes and beliefs associated with using dissection in the general science classroom. Additional perspectives are represented, and incorporated into the literature review, by interviews with experts in the fields of solid waste management and conservation biology

Audiometric Assessment for Children aged 6 to 60 months

This protocol addresses procedures for audiometric assessment of hearing thresholds in infants and young children using behavioural measures of threshold and associated measures in a test battery. The scope of this document includes these assessments as funded by MCCSS for the Ontario Infant Hearing Program (IHP). In infants and young children, modified operant conditioning is used to obtain systematic behavioural responses to sound from older infants and young children. These conditioned responses are used as the basis of behavioural audiometry until the child is developmentally able to complete standard audiometry, at about 3 to 5 years of age in typically developing children (Sabo et al., 2003)

Theta-burst stimulation and frontotemporal regulation of cardiovascular autonomic outputs : the role of state anxiety

Dysregulation of autonomic cardiovascular homeostasis is an important cardiological and neurological risk factor. Cortical regions including the prefrontal and insular cortices exert tonic control over cardiovascular autonomic functions. Transcranial Magnetic Stimulation (TMS) may be a suitable approach for studying top-down control of visceromotor processes. However, there is inconsistent evidence as to whether TMS can modify cardiovascular autonomic states. One reason for the inconsistency may arise from the lack of studies accounting for the acute affective states of participants with respect to the stimulation procedures. To gain more insights into these processes, we evaluated the effects of intermittent and continuous theta-burst stimulation (TBS) to the right frontotemporal cortex on state anxiety and cardiovascular responses in a preliminary study. State anxiety significantly increased for both intermittent and continuous TBS relative to sham. Intermittent TBS also significantly increased heart-rate variability (HRV) at natural and slow-paced breathing rates. The effect of intermittent TBS on vagally-mediated HRV was attenuated after accounting for stimulation-induced anxiety, suggesting that increased HRV after stimulation may reflect a response to a transient stressor (i.e., the stimulation itself), rather than TBS effects on visceromotor networks. In contrast, continuous TBS increased pulse transit time latency across breathing rates, an effect that was enhanced after accounting for state anxiety. TMS is a promising approach to study cortical involvement in cardiovascular autonomic regulation. The findings show that TBS induces effects on visceromotor networks, and that analysis of state covariates such as anxiety can be important for increasing the precision of these estimates. Future non-invasive brain stimulation studies of top-down neurocardiac regulation should account for the potential influence of non-specific arousal or anxiety responses to stimulation

Protocol for Audiological Surveillance of Children at Risk for Permanent Hearing Loss

This document addresses procedures for the audiological surveillance of hearing of infants and young children at risk for late onset or progressive permanent hearing loss (PHL). It is closely linked with the Ontario Infant Hearing Program (IHP) Protocol for Universal Newborn Hearing Screening Auditory Brainstem Response Assessment (ABRA) Protocol, and the IHP protocol for Audiometric Assessment for Children Aged 6 to 60 Months with respect to risk indicators, hearing screening technology applied, screening bypass, and audiological assessment procedures

Corticomuscular synchronization with small and large dynamic force output

BACKGROUND: Over the last years much research has been devoted to investigating the synchronization between cortical motor and muscular activity as measured by EEG/MEG-EMG coherence. The main focus so far has been on corticomuscular coherence (CMC) during static force condition, for which coherence in beta-range has been described. In contrast, we showed in a recent study [1] that dynamic force condition is accompanied by gamma-range CMC. The modulation of the CMC by various dynamic force amplitudes, however, remained uninvestigated. The present study addresses this question. We examined eight healthy human subjects. EEG and surface EMG were recorded simultaneously. The visuomotor task consisted in isometric compensation for 3 forces (static, small and large dynamic) generated by a manipulandum. The CMC, the cortical EEG spectral power (SP), the EMG SP and the errors in motor performance (as the difference between target and exerted force) were analyzed. RESULTS: For the static force condition we found the well-documented, significant beta-range CMC (15-30Hz) over the contralateral sensorimotor cortex. Gamma-band CMC (30-45Hz) occurred in both small and large dynamic force conditions without any significant difference between both conditions. Although in some subjects beta-range CMC was observed during both dynamic force conditions no significant difference between conditions could be detected. With respect to the motor performance, the lowest errors were obtained in the static force condition and the highest ones in the dynamic condition with large amplitude. However, when we normalized the magnitude of the errors to the amplitude of the applied force (relative errors) no significant difference between both dynamic conditions was observed. CONCLUSIONS: These findings confirm that during dynamic force output the corticomuscular network oscillates at gamma frequencies. Moreover, we show that amplitude modulation of dynamic force has no effect on the gamma CMC in the low force range investigated. We suggest that gamma CMC is rather associated with the internal state of the sensorimotor system as supported by the unchanged relative error between both dynamic conditions

Individual resting-state frontocingular functional connectivity predicts the intermittent theta burst stimulation response to stress in healthy female volunteers

Intermittent theta burst stimulation (iTBS) delivered to the dorsolateral prefrontal cortex (DLPFC) has been investigated as a promising treatment for stress and stress‐related mental disorders such as major depression, yet large individual differences in responsiveness demand further exploration and optimization of its effectiveness. Clinical research suggests that resting‐state functional connectivity (rsFC) between the DLPFC and the anterior cingulate cortex (ACC) can predict iTBS treatment response in depression. The present study aimed to investigate whether rsFC between the left DLPFC and ACC subregions could predict the degree to which the stress system is affected by iTBS. After assessment of baseline resting‐state fMRI data, 34 healthy female participants performed the Trier Social Stress Test on two separate days, each followed by active or sham iTBS over the left DLPFC. To evaluate iTBS effects on the stress‐system, salivary cortisol was measured throughout the procedure. Our results showed that a stronger negative correlation between the left DLPFC and the caudal ACC was linked to a larger attenuation of stress‐system sensitivity during active, but not during sham iTBS. In conclusion, based on individual rsFC between left DLPFC and caudal ACC, iTBS could be optimized to more effectively attenuate deregulation of the stress system

Voluntary Wheel Running in Old C57BL/6 Mice Reduces Age-Related Inflammation in the Colon but Not in the Brain

Inflammation is considered a possible cause of cognitive decline during aging. This study investigates the influence of physical activity and social isolation in old mice on their cognitive functions and inflammation. The Barnes maze task was performed to assess spatial learning and memory in 3, 9, 15, 24, and 28 months old male C57BL/6 mice as well as following voluntary wheel running (VWR) and social isolation (SI) in 20 months old mice. Inflammatory gene expression was analyzed in hippocampal and colonic samples by qPCR. Cognitive decline occurs in mice between 15 and 24 months of age. VWR improved cognitive functions while SI had negative effects. Expression of inflammatory markers changed during aging in the hippocampus ( Il1a / Il6 / S100b / Iba1 / Adgre1 / Cd68 / Itgam ) and colon ( Tnf / Il6 / Il1ra / P2rx7 ). VWR attenuates inflammaging specifically in the colon ( Ifng / Il10 / Ccl2 / S100b / Iba1 ), while SI regulates intestinal Il1b and Gfap . Inflammatory markers in the hippocampus were not altered following VWR and SI. The main finding of our study is that both the hippocampus and colon exhibit an increase in inflammatory markers during aging, and that voluntary wheel running in old age exclusively attenuates intestinal inflammation. Based on the existence of the gut-brain axis, our results extend therapeutic approaches preserving cognitive functions in the elderly to the colon

Effects of HF-rTMS over the left and right DLPFC on proactive and reactive cognitive control

Previous research supports the distinction between proactive and reactive control. Although the dorsolateral prefrontal cortex (DLPFC) has been consistently related to these processes, lateralization of proactive and reactive control is still under debate. We manipulated brain activity to investigate the role of the left and right DLPFC in proactive and reactive cognitive control. Using a single-blind, sham-controlled crossover within-subjects design, 25 young healthy females performed the 'AX' Continuous Performance Task after receiving sham vs active high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) to increase left and right DLPFC activity. Reaction times (RTs) and pupillometry were used to assess patterns of proactive and reactive cognitive control and task-related resource allocation, respectively. We observed that, compared to sham, HF-rTMS over the left DLPFC increased proactive control. After right DLPFC HF-rTMS, participants showed slower RTs on AX trials, suggesting more reactive control. However, this latter result was not supported by RTs on BX trials (i.e. the trial that specifically assess reactive control). Pupil measures showed a sustained increase in resource allocation after both active left and right HF-rTMS. Our results with RT data provide evidence on the role of the left DLPFC in proactive control and suggest that the right DLPFC is implicated in reactive control

The Effect of PCSK1 Variants on Waist, Waist-Hip Ratio and Glucose Metabolism Is Modified by Sex and Glucose Tolerance Status

on measures of body fat and glucose homeostasis in Danish individuals and to assess interactions of genotypes with age, sex and glucose tolerance status. Data were included in meta-analyses of additional Europeans. = 0.02) elevated level of acute insulin response for this variant. Finally, we found that the rs6232 G-allele associated with higher levels of GLP-1, GLP-2 and glucagon and that the rs6235 C-allele associated with higher levels of GIP and glucagon during a meal-test. rs6232 G-allele and rs6235 C-allele have an effect on body composition which may be modified by sex, whereas the effect of rs6235 C-allele on fasting and stimulated circulating plasma glucose and hormone levels may be influenced by glucose tolerance status

The influence of personality on the effect of iTBS after being stressed on cortisol secretion

Over the last years, individualization of repetitive Transcranial Magnetic Stimulation (rTMS) parameters has been a focus of attention in the field of non-invasive stimulation. It has been proposed that in stress-related disorders personality characteristics may influence the clinical outcome of rTMS. However, the underlying physiological mechanisms as to how personality may affect the rTMS response to stress remains to be clarified. In this sham-controlled crossover study, after being stressed by the Trier Social Stress Test, 38 healthy females received two sessions of intermittent theta burst stimulation (iTBS) applied to the left dorsolateral prefrontal cortex. To take possible personality influences into account, they also completed the Temperament and Character Inventory. Mood and salivary cortisol were assessed throughout the experimental protocol. Overall, two iTBS sessions did not significantly alter mood or influenced cortisol secretion. When taking into account personality features, higher scores on the character dimension Cooperativeness was related to decreased cortisol output, only when active iTBS was administered after the social stressor. In line with other studies, personality features such as the character dimension Cooperativeness may be of particular interest to explain individual neurobiological responses to neurostimulation