<P>To examine the effects of purported fiber-type transformation following spinal cord injury (SCI), twitch contractile properties of the soleus, tibialis anterior (TA) and thenar muscles were examined in individuals with chronic (> 4 years) SCI. Furthermore, the force-frequency relationship, fatigue and posttetanic potentiation (PTP) of the paralyzed TA muscle were also evaluated. Nine adults with SCI (22-59 yrs; lesion level C3-T2) and 9 age-and gender-matched able-bodied controls (AB) participated in this study.</P><P>On the first visit to the laboratory, the maximum twitch response for all three muscles was determined by delivering a series of single stimuli with gradually increasing intensity. For evaluation of PTP, tetanic stimulation (100Hz) was applied to the TA for 5 seconds followed by single twitches delivered at 5 seconds after tetanus and then at 30-second intervals for 4 minutes posttetanus. On a second visit, the force-frequency relationship (FFR) and 15Hz fatigue of the TA was evaluated. One second bursts ranging from 1-1OOHz were delivered randomly with 2 minutes of rest in between each frequency for assessment of FFR. Following a 1 0-minute rest period, the first fatigue protocol was given, consisting of 1-minute of tetanic stimulation at 15Hz. At the third session, the 30Hz fatigue of the TA was performed, consisting of 1-minute of tetanic stimulation at 30Hz.</P><P>In the soleus muscle, the AB had a higher peak twitch torque (PT) and M-wave amplitude compared to.the SCI group (14.2 ± 3.9Nm vs. 8.9 ± 6.1Nm; p = 0.058, and 13.5 ± 5.3mV and 5.5 ± 4.0mV; p < 0.05, respectively). Contractile speed was not significantly different between groups. Time to peak torque (TPT) was longer in AB (111.5 ± 15.4ms) compared to the SCI (76.7 ± 25.0ms; p<0.05) due to the larger twitches; however, the rates of torque development (RTD) were similar between groups. In the TA muscle, AB and SCI had similar PT (2.8 ± 0.5Nm and 3.2 ± 1.2Nm, respectively). TA contractile properties were faster in SCI, as seen by significantly shorter TPT and faster RTD (p<0.05). M-wave amplitude of AB was significantly greater than the SCI group, 8.3 ± 2.6mV versus 4.2 ± 1.7mV, respectively (p<0.05). Finally, in the thenar muscle, PT appeared to be smaller in AB compared to SCI, 1.7 ± 0.8Nm versus 2.9 ± 1.3Nm, respectively (p = 0.094). The RTD was faster in the SCI group compared to AB (p<0.05).</P><P>Evaluation of FFR revealed that the curve of the SCI was shifted to the left of that of AB. The F50 (frequency required to elicit 50% of maximum peak torque) was significantly lower in the SCI compared to AB, 6.7 ± 3.4Hz and 16.7 ± 4.1Hz, respectively (p<0.05). Following the fatigue protocols, SCI group tended to fatigue more rapidly and to a greater extent than AB at both frequencies, however this was only significant at 15Hz. The M-wave declined with fatigue (30Hz) in both groups, but this decline tended to be more rapid in SCI.</P><P>For the assessment of PTP, both groups started off with similar baseline twitches in their TA muscle (2.7 ± 0.3Nm and 2.9 ± 0.8Nm, respectively). At 5 seconds following tetanus, PT was significantly greater in both groups, but the amount of potentiation was greater in SCI versus AB (p = 0.058). Over the 4-min recovery period, PT declined in both groups until it was no longer significantly greater than baseline by 3 minutes 30 seconds. The potentiated twitch of both groups was faster than at baseline. RTD increased significantly by an average of 56% in the AB group and 91% in the SCI group and was significantly greater in SCI compared with AB at 30-150 seconds post-tetanus (p<0.05). At 5 seconds post-tetanus, RTR was significantly faster in both groups and had increased by 77% and 53% in the AB and SCI groups, respectively. The recovery ofRTD and R TR over the 4 minutes occurred more rapidly in AB versus SCI.</P><P>In conclusion, changes in contractile properties following SCI differ between muscle groups; faster contractile properties indicative of fiber type transformation are more evident in TA and thenar muscle groups, compared with the soleus. The smaller M-waves seen in the lower extremities support the significant muscle atrophy following SCI. Furthermore, the predicted transformation towards a higher proportion of fast-twitch fibers following paralysis was supported by a trend for decreased fatigue resistance and significantly greater PTP in the SCI group. The FFR data, however, did not support this predicted fiber type transformation, shifting to the left instead of the right. This leftward shift of FFR has been reported in other paralyzed human muscle presenting with faster contractile speeds; the mechanisms behind this warrant further investigation.</P> / Thesis / Master of Science (MSc)

Injuries to the lower extremity are frequent and severe in frontal automotive collisions, often leading to pain and long-term impairment. Most injury criteria developed for the lower extremity are conducted with the foot and ankle in a neutral posture, do not take into account footwear, and assess injury risk to the entire lower extremity at the tibia. An instrumented boot, designed to address some of these challenges, was calibrated over a range of impact energies expected in frontal automotive collisions. A dynamic calibration method was developed to convert changes in voltage across a piezoresistive polymer to the applied axial force. The instrumented boot was then used to examine the axial impact response of two commonly used Anthropomorphic Test Device (ATD) lower legs, under altered ankle postures. Both posture and ATD model were found to affect the load distribution on the foot, highlighting the need to establish injury limits for non-neutral postures as well as selecting the appropriate ATD model. The instrumented boot provided regional loading information that was not reflected in standard industry metrics, emphasizing the importance of increased instrumentation in this area. A technique was developed for mounting cadaveric feet to ATD tibia shafts, in order to gather industry-relevant load data while examining the impact characteristics of the foot. Load data were collected at the plantar surface of the foot using the instrumented boot, as well as the tibia load cells in the ATD shaft, that highlighted differences in load transmission through cadaveric and ATD feet. Understanding the impact characteristics of ATDs under non-standard ankle postures as well as examining the load transmission through cadaveric feet highlighted some shortcomings with current injury assessment techniques. The results of this work can be used to improve future collision testing practices, in order to reduce the incidence of lower extremity injuries. / Thesis / Master of Applied Science (MASc) / Foot and ankle injuries are common in automotive collisions and often lead to pain and long-term impairment. Experimental work on these types of injuries is traditionally conducted with the foot and ankle positioned in a neutral ankle posture, which does not reflect the range of ankle postures individuals may assume in a car crash. The purpose of this work was to use biomechanical tools to assess foot/ankle injury risk. Impact testing was performed on two commonly used crash test dummy lower legs in conditions relevant to those experienced in car crashes. A technique was developed to mount cadaveric feet to crash test dummy tibias to gather injury information of the foot, while also collecting load data in the tibia shaft – relevant metrics for industry crash testing. The results of this work outline the shortcomings of traditional injury assessment methods and may be used to improve future practices.

Background: Patients with non-penetrating traumatic brain injuries (TBI) are at high risk for damage to ventral prefrontal brain regions, due to the brain’s acceleration into the bony ridges of the anterior portions of the skull. Current neuropsychological assessments of these patients focus mainly on the assessment of so-called “executive functions,” which are associated with dorsolateral prefrontal regions. Ventral prefrontal pathology is more likely to disrupt social and emotional functions, but assessments of these abilities using objective measurements that require patients to demonstrate their competence are rare. Mounting evidence suggests that chronic social and emotional deficits are common in TBI, and that these difficulties result in significant functional impairments post-injury, making clear the need to develop and use objective assessment tools during clinical neuropsychological assessments. Methods: In the current project, the Global Interpersonal Skills Test (GIST), a questionnaire measure of social skills with both a self-rated and an informant-rated version, was developed, along with three novel or adapted performance-based measures of social and emotional functioning. The first novel measure was the Assessments of Social Context (ASC), a video-based task examining comprehension of social context using non-verbal cues, including the identification of emotions, intensions and positive or negative attitudes of one person towards another. The second task was the Awareness of Interoception Test (AIT), a heartbeat detection paradigm adapted from previous literature that measures participants’ sensitivity to their cardiac function, which is implicated in basic emotional functioning. The third task was the Social Interpretations Task (SIT), an animation-based task adapted from previous literature examining participants’ ability to apply a social interpretation to stimuli that are not inherently social in nature. All novel tasks were developed and piloted with healthy undergraduates. A group of patients with moderate to severe TBI (N = 16), and a group of non-brain damaged controls (N = 16) underwent neuropsychological testing. Standard neuropsychological measures including the Wechsler Test of Adult Reading, Digit Span and Digit Symbol Coding from the Wechsler Adult Intelligence Scale, phonemic (FAS) and semantic fluency (Animals) from the Verbal Fluency Test, and the Trail Making Test, as well as the novel measures to both patients with TBI and controls were administered. The following predictions were made: vi 1) The novel performance-based measures of social abilities would be more sensitive to the presence of moderate and severe TBI than the standard neuropsychological measures of cognition; 2) On the informant version of the GIST, but not the self-report version, patients would have scores than controls; 3) Patients’ performance on the ASC would be less accurate than controls’, and this difference would be associated with real-world social skills, measured by the informant-version of the GIST; 4) Patients’ AIT performance would be less accurate than controls’, and this would be related to their self-rated emotional changes; 5) Patients’ SIT performance would be less accurate than controls’, and this difference would be associated with real-world social skills, again measured by the informant-version of the GIST. Findings: Findings were consistent with these hypotheses: 1) A statistically significant logistic regression revealed that a Social composite variable comprising the ASC, AIT and SIT was more sensitive to the presence of TBI (β = 9.59, p < .05) than a Cognitive composite variable comprising Digit Symbol Coding, Trails B completion time, and Phonemic Fluency (β = 0.006, p = .466). 2) A multivariate analysis of variance (MANOVA) revealed that informants of patients gave lower GIST scores to patients than the informants of controls (F(1,28) = 22.2, p < 0.0001), whereas there were no differences between groups on the self-rated version of the GIST (F(1,28) = .35, p = .56); 3) Patients’ ASC performance was significantly poorer than controls’ on a MANOVA (F(1,31) = 21.7, p < .0001), and ASC total scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .624, p < .0001). 4) Patients’ AIT performance was significantly poorer than controls’ using an independent samples t test (t(13) = 1.43, p < 0.005), and qualitative investigation of subjective reports of emotional change among patients suggested a potential relationship between emotional changes and AIT performance. vii 5) Patients’ SIT performance was significantly poorer than controls on an independent samples t test (t(30) = -2.12, p < 0.05), and SIT scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .460, p < .0001). Interpretation: This research represents a preliminary step in the development of clinically useful measures of social and emotional difficulties following TBI. Given the small sample size of the patient group, and the presence of co-morbid difficulties among some of the participants in this research, further testing of these measures in larger, more homogeneous samples would strengthen the current results, as would using a comparison group of people with milder TBI, rather than neuro-typical controls. The complexity of social behaviour requires that the current measures be further validated against other real-world assessments of social ability, and that assessments of other aspects of social behaviour be conducted. Nonetheless, the measures described here are a promising start to supplementing the neuropsychological toolkit in an area that requires further development at the present time.

Background: Patients with non-penetrating traumatic brain injuries (TBI) are at high risk for damage to ventral prefrontal brain regions, due to the brain’s acceleration into the bony ridges of the anterior portions of the skull. Current neuropsychological assessments of these patients focus mainly on the assessment of so-called “executive functions,” which are associated with dorsolateral prefrontal regions. Ventral prefrontal pathology is more likely to disrupt social and emotional functions, but assessments of these abilities using objective measurements that require patients to demonstrate their competence are rare. Mounting evidence suggests that chronic social and emotional deficits are common in TBI, and that these difficulties result in significant functional impairments post-injury, making clear the need to develop and use objective assessment tools during clinical neuropsychological assessments. Methods: In the current project, the Global Interpersonal Skills Test (GIST), a questionnaire measure of social skills with both a self-rated and an informant-rated version, was developed, along with three novel or adapted performance-based measures of social and emotional functioning. The first novel measure was the Assessments of Social Context (ASC), a video-based task examining comprehension of social context using non-verbal cues, including the identification of emotions, intensions and positive or negative attitudes of one person towards another. The second task was the Awareness of Interoception Test (AIT), a heartbeat detection paradigm adapted from previous literature that measures participants’ sensitivity to their cardiac function, which is implicated in basic emotional functioning. The third task was the Social Interpretations Task (SIT), an animation-based task adapted from previous literature examining participants’ ability to apply a social interpretation to stimuli that are not inherently social in nature. All novel tasks were developed and piloted with healthy undergraduates. A group of patients with moderate to severe TBI (N = 16), and a group of non-brain damaged controls (N = 16) underwent neuropsychological testing. Standard neuropsychological measures including the Wechsler Test of Adult Reading, Digit Span and Digit Symbol Coding from the Wechsler Adult Intelligence Scale, phonemic (FAS) and semantic fluency (Animals) from the Verbal Fluency Test, and the Trail Making Test, as well as the novel measures to both patients with TBI and controls were administered. The following predictions were made: vi 1) The novel performance-based measures of social abilities would be more sensitive to the presence of moderate and severe TBI than the standard neuropsychological measures of cognition; 2) On the informant version of the GIST, but not the self-report version, patients would have scores than controls; 3) Patients’ performance on the ASC would be less accurate than controls’, and this difference would be associated with real-world social skills, measured by the informant-version of the GIST; 4) Patients’ AIT performance would be less accurate than controls’, and this would be related to their self-rated emotional changes; 5) Patients’ SIT performance would be less accurate than controls’, and this difference would be associated with real-world social skills, again measured by the informant-version of the GIST. Findings: Findings were consistent with these hypotheses: 1) A statistically significant logistic regression revealed that a Social composite variable comprising the ASC, AIT and SIT was more sensitive to the presence of TBI (β = 9.59, p < .05) than a Cognitive composite variable comprising Digit Symbol Coding, Trails B completion time, and Phonemic Fluency (β = 0.006, p = .466). 2) A multivariate analysis of variance (MANOVA) revealed that informants of patients gave lower GIST scores to patients than the informants of controls (F(1,28) = 22.2, p < 0.0001), whereas there were no differences between groups on the self-rated version of the GIST (F(1,28) = .35, p = .56); 3) Patients’ ASC performance was significantly poorer than controls’ on a MANOVA (F(1,31) = 21.7, p < .0001), and ASC total scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .624, p < .0001). 4) Patients’ AIT performance was significantly poorer than controls’ using an independent samples t test (t(13) = 1.43, p < 0.005), and qualitative investigation of subjective reports of emotional change among patients suggested a potential relationship between emotional changes and AIT performance. vii 5) Patients’ SIT performance was significantly poorer than controls on an independent samples t test (t(30) = -2.12, p < 0.05), and SIT scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .460, p < .0001). Interpretation: This research represents a preliminary step in the development of clinically useful measures of social and emotional difficulties following TBI. Given the small sample size of the patient group, and the presence of co-morbid difficulties among some of the participants in this research, further testing of these measures in larger, more homogeneous samples would strengthen the current results, as would using a comparison group of people with milder TBI, rather than neuro-typical controls. The complexity of social behaviour requires that the current measures be further validated against other real-world assessments of social ability, and that assessments of other aspects of social behaviour be conducted. Nonetheless, the measures described here are a promising start to supplementing the neuropsychological toolkit in an area that requires further development at the present time.

Background: Patients with non-penetrating traumatic brain injuries (TBI) are at high risk for damage to ventral prefrontal brain regions, due to the brain’s acceleration into the bony ridges of the anterior portions of the skull. Current neuropsychological assessments of these patients focus mainly on the assessment of so-called “executive functions,” which are associated with dorsolateral prefrontal regions. Ventral prefrontal pathology is more likely to disrupt social and emotional functions, but assessments of these abilities using objective measurements that require patients to demonstrate their competence are rare. Mounting evidence suggests that chronic social and emotional deficits are common in TBI, and that these difficulties result in significant functional impairments post-injury, making clear the need to develop and use objective assessment tools during clinical neuropsychological assessments. Methods: In the current project, the Global Interpersonal Skills Test (GIST), a questionnaire measure of social skills with both a self-rated and an informant-rated version, was developed, along with three novel or adapted performance-based measures of social and emotional functioning. The first novel measure was the Assessments of Social Context (ASC), a video-based task examining comprehension of social context using non-verbal cues, including the identification of emotions, intensions and positive or negative attitudes of one person towards another. The second task was the Awareness of Interoception Test (AIT), a heartbeat detection paradigm adapted from previous literature that measures participants’ sensitivity to their cardiac function, which is implicated in basic emotional functioning. The third task was the Social Interpretations Task (SIT), an animation-based task adapted from previous literature examining participants’ ability to apply a social interpretation to stimuli that are not inherently social in nature. All novel tasks were developed and piloted with healthy undergraduates. A group of patients with moderate to severe TBI (N = 16), and a group of non-brain damaged controls (N = 16) underwent neuropsychological testing. Standard neuropsychological measures including the Wechsler Test of Adult Reading, Digit Span and Digit Symbol Coding from the Wechsler Adult Intelligence Scale, phonemic (FAS) and semantic fluency (Animals) from the Verbal Fluency Test, and the Trail Making Test, as well as the novel measures to both patients with TBI and controls were administered. The following predictions were made: vi 1) The novel performance-based measures of social abilities would be more sensitive to the presence of moderate and severe TBI than the standard neuropsychological measures of cognition; 2) On the informant version of the GIST, but not the self-report version, patients would have scores than controls; 3) Patients’ performance on the ASC would be less accurate than controls’, and this difference would be associated with real-world social skills, measured by the informant-version of the GIST; 4) Patients’ AIT performance would be less accurate than controls’, and this would be related to their self-rated emotional changes; 5) Patients’ SIT performance would be less accurate than controls’, and this difference would be associated with real-world social skills, again measured by the informant-version of the GIST. Findings: Findings were consistent with these hypotheses: 1) A statistically significant logistic regression revealed that a Social composite variable comprising the ASC, AIT and SIT was more sensitive to the presence of TBI (β = 9.59, p < .05) than a Cognitive composite variable comprising Digit Symbol Coding, Trails B completion time, and Phonemic Fluency (β = 0.006, p = .466). 2) A multivariate analysis of variance (MANOVA) revealed that informants of patients gave lower GIST scores to patients than the informants of controls (F(1,28) = 22.2, p < 0.0001), whereas there were no differences between groups on the self-rated version of the GIST (F(1,28) = .35, p = .56); 3) Patients’ ASC performance was significantly poorer than controls’ on a MANOVA (F(1,31) = 21.7, p < .0001), and ASC total scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .624, p < .0001). 4) Patients’ AIT performance was significantly poorer than controls’ using an independent samples t test (t(13) = 1.43, p < 0.005), and qualitative investigation of subjective reports of emotional change among patients suggested a potential relationship between emotional changes and AIT performance. vii 5) Patients’ SIT performance was significantly poorer than controls on an independent samples t test (t(30) = -2.12, p < 0.05), and SIT scores were significantly correlated with GIST informant scores, using Spearman’s rank-order correlations (ρ(31) = .460, p < .0001). Interpretation: This research represents a preliminary step in the development of clinically useful measures of social and emotional difficulties following TBI. Given the small sample size of the patient group, and the presence of co-morbid difficulties among some of the participants in this research, further testing of these measures in larger, more homogeneous samples would strengthen the current results, as would using a comparison group of people with milder TBI, rather than neuro-typical controls. The complexity of social behaviour requires that the current measures be further validated against other real-world assessments of social ability, and that assessments of other aspects of social behaviour be conducted. Nonetheless, the measures described here are a promising start to supplementing the neuropsychological toolkit in an area that requires further development at the present time.

Le droit de la concurrence est régi, principalement, par le droit de l’Union européenne. Le "public enforcement" garantit le respect de ce dernier. Le droit de l’Union européenne ne prévoyait pas jusqu’alors de régime juridique permettant aux victimes de pratiques anticoncurrentielles d’obtenir réparation de leur préjudice, malgré une reconnaissance jurisprudentielle. Le droit national, quant à lui, n’avait pas de régime spécifique et les victimes de pratiques anticoncurrentielles se voyaient appliquer le régime commun de la responsabilité délictuelle sur le fondement de l’article 1382 ancien du Code civil. Vu la complexité du contentieux, cette situation entraînait de grandes difficultés pour les victimes d’obtenir réparation des dommages subis. La directive n°2014/104/UE a créé un régime juridique nouveau et a harmonisé le "private enforcement". Elle a été transposée en droit français par l’ordonnance n°2017-303. Cette réforme très attendue est en demi-teinte. Certes, il existe des avancées non négligeables. La directive facilite la preuve de la faute et organise la communication et la production de pièces pendant l’instance. Elle consacre une présomption de dommage et encadre l’évaluation du préjudice. En revanche, la réforme est plutôt timorée sur d’autres éléments, tels que la faute, l’imputation de la faute, ou encore le financement des actions. Cette étude a pour objectif d’analyser ces nouvelles dispositions afin de vérifier si la directive facilite effectivement les actions en dommages et intérêts pour les infractions au droit de la concurrence. / Competition law is mainly governed by European Union law. Public enforcement ensures fulfilment of EU law. Until recently, and despite recognition in case-law, EU law did not provide for a legal regime enabling victims of anti-competitive practices to obtain compensation of their damage. National law did not have a specific legal regime and victims of anti-competitive practices could apply the common civil liability regime on the basis of ex-Article 1382 of the Civil Code. Given the complexity of litigation, this situation lead to great difficulties for victims to obtain compensation for their damages. EU directive n°2014/104 creates a new legal regime and harmonizes the private enforcement. It has been transposed into French law under ordonnance n°2017-303. This much-awaited reform is subdued. Certainly, there are significant progresses. The directive facilitates the proof of fault, and organizes the communication and production of documents during the proceedings. It establishes a presumption of loss and provides a framework to assess the harm. On the other hand, the reform is rather timid on other elements, such as the fault, its attribution, or the financing of the actions. The purpose of this study is to analyze these new rules to ascertain whether it effectively facilitates actions for damages for infringements of competition law.