title: Duty factor is a viable measure to classify spontaneous running forms

authors: Patoz, Aurélien

subjects: biomechanics

abstract: Runners were classified using two different methods based on their spontaneous running form: (1) subjectively using the V®score from the Volodalen® scale, leading to terrestrial and aerial groups; and (2) objectively using the duty factor (DF), leading to high (DFhigh) and low (DFlow) DF groups. This study aimed to compare these two classification schemes. Eighty-nine runners were divided in two groups using the V®score (VOL groups) and were also ranked according to their DF. They ran on a treadmill at 12 km·h⁻¹ with simultaneous recording of running kinematics, using a three-dimensional motion capture system. DF was computed from data as the ratio of ground contact time to stride time. The agreement (95% confidence interval) between VOL and DF groups was 79.8% (69.9%, 87.6%), with relatively high sensitivity (81.6% (68.0%, 91.2%)) and specificity (77.5% (61.6%, 89.2%)). Our results suggest that the DF and V®score reflect similar constructs and lead to similar subgroupings of spontaneous running form (aerial runners if DF < 27.6% and terrestrial runners if DF > 28.8% at 12 km·h⁻¹). These results suggest that DF could be a useful objective measure to monitor real-time changes in spontaneous running form using wearable technology. As a forward-looking statement, spontaneous changes in running form during racing or training could assist in identifying fatigue or changes in environmental conditions, allowing for a better understanding of runners.

text: Duty factor is a viable measure to classify spontaneous running forms Runners were classified using two different methods based on their spontaneous running form: (1) subjectively using the V®score from the Volodalen® scale, leading to terrestrial and aerial groups; and (2) objectively using the duty factor (DF), leading to high (DFhigh) and low (DFlow) DF groups. This study aimed to compare these two classification schemes. Eighty-nine runners were divided in two groups using the V®score (VOL groups) and were also ranked according to their DF. They ran on a treadmill at 12 km·h⁻¹ with simultaneous recording of running kinematics, using a three-dimensional motion capture system. DF was computed from data as the ratio of ground contact time to stride time. The agreement (95% confidence interval) between VOL and DF groups was 79.8% (69.9%, 87.6%), with relatively high sensitivity (81.6% (68.0%, 91.2%)) and specificity (77.5% (61.6%, 89.2%)). Our results suggest that the DF and V®score reflect similar constructs and lead to similar subgroupings of spontaneous running form (aerial runners if DF < 27.6% and terrestrial runners if DF > 28.8% at 12 km·h⁻¹). These results suggest that DF could be a useful objective measure to monitor real-time changes in spontaneous running form using wearable technology. As a forward-looking statement, spontaneous changes in running form during racing or training could assist in identifying fatigue or changes in environmental conditions, allowing for a better understanding of runners.

year: 2019

title: Subthreshold dynamics of a single neuron from a Hamiltonian perspective

authors: Wilson, Marcus T.

subjects: brain models

abstract: We use Hamilton's equations of classical mechanics to investigate the behavior of a cortical neuron on the approach to an action potential. We use a two-component dynamic model of a single neuron, due to Wilson, with added noise inputs. We derive a Lagrangian for the system, from which we construct Hamilton's equations. The conjugate momenta are found to be linear combinations of the noise input to the system. We use this approach to consider theoretically and computationally the most likely manner in which such a modeled neuron approaches a firing event. We find that the firing of a neuron is a result of a drop in inhibition, due to a temporary increase in negative bias of the mean noise input to the inhibitory control equation. Moreover, we demonstrate through theory and simulation that, on average, the bias in the noise increases in an exponential manner on the approach to an action potential. In the Hamiltonian description, an action potential can therefore be considered a result of the exponential growth of the conjugate momenta variables pulling the system away from its equilibrium state, into a nonlinear regime.

text: Subthreshold dynamics of a single neuron from a Hamiltonian perspective We use Hamilton's equations of classical mechanics to investigate the behavior of a cortical neuron on the approach to an action potential. We use a two-component dynamic model of a single neuron, due to Wilson, with added noise inputs. We derive a Lagrangian for the system, from which we construct Hamilton's equations. The conjugate momenta are found to be linear combinations of the noise input to the system. We use this approach to consider theoretically and computationally the most likely manner in which such a modeled neuron approaches a firing event. We find that the firing of a neuron is a result of a drop in inhibition, due to a temporary increase in negative bias of the mean noise input to the inhibitory control equation. Moreover, we demonstrate through theory and simulation that, on average, the bias in the noise increases in an exponential manner on the approach to an action potential. In the Hamiltonian description, an action potential can therefore be considered a result of the exponential growth of the conjugate momenta variables pulling the system away from its equilibrium state, into a nonlinear regime.

year: 2008

title: KAUMĀTUATANGA  Supporting School Leaders To Develop Cultural Values While Resisting The Dominance of Colonialism

authors: Nuri, Ngahuia

subjects: Kaumātua

abstract: In an education system that is asserting to the importance of Māori (indigenous people of Aotearoa) language, culture, identity and the history of Aotearoa  (New Zealand) into the curriculum, there is direction from the Ministry of Education (MOE) for schools to reach out to iwi. What this looks like and how this can be achieved is not an easy task. This thesis follows the journey of three kaumātua (respected, knowledgeable elders, both female and male) working alongside the Senior Leadership Team (SLT) of a decile 10 kura auraki (mainstream primary school) where ākonga Māori (Māori students) were in the minority. The research examines what role kaumātua might have in guiding other schools to help tamariki Māori (Māori children) enjoy and achieve education success as Māori. It highlights the coming together of leaders from two different worldviews with this vision as a common purpose. 

Kaumātua in te ao Māori (the Māori world) are respected elders. Kaumātua are leaders, respected for their wisdom, knowledge and models of behaviour among other attributes. The Māui narratives are one example of demonstrating the characteristics of kaumātua. It was through his respected elders that Maui achieved so much. It was his grandfather who rescued him and taught him all he knew. It was his grandmother Mahuika who gave him fire and it was his kuia (female elder) Murirangiwhenua from whom he received the magic jawbone. The wisdom of Māori kaumātua has been recognised for centuries by Māori and yet kaumātua are often an untapped resource in the mainstream sector of education. In this thesis the kaumātua and members of the SLT share their experiences of working together and the learning and unlearning that has taken place over a period of four years from 2016 through 2019. They share their vulnerability, humility and strength in the goals they have worked towards over this period of time.

text: KAUMĀTUATANGA  Supporting School Leaders To Develop Cultural Values While Resisting The Dominance of Colonialism In an education system that is asserting to the importance of Māori (indigenous people of Aotearoa) language, culture, identity and the history of Aotearoa  (New Zealand) into the curriculum, there is direction from the Ministry of Education (MOE) for schools to reach out to iwi. What this looks like and how this can be achieved is not an easy task. This thesis follows the journey of three kaumātua (respected, knowledgeable elders, both female and male) working alongside the Senior Leadership Team (SLT) of a decile 10 kura auraki (mainstream primary school) where ākonga Māori (Māori students) were in the minority. The research examines what role kaumātua might have in guiding other schools to help tamariki Māori (Māori children) enjoy and achieve education success as Māori. It highlights the coming together of leaders from two different worldviews with this vision as a common purpose. 

Kaumātua in te ao Māori (the Māori world) are respected elders. Kaumātua are leaders, respected for their wisdom, knowledge and models of behaviour among other attributes. The Māui narratives are one example of demonstrating the characteristics of kaumātua. It was through his respected elders that Maui achieved so much. It was his grandfather who rescued him and taught him all he knew. It was his grandmother Mahuika who gave him fire and it was his kuia (female elder) Murirangiwhenua from whom he received the magic jawbone. The wisdom of Māori kaumātua has been recognised for centuries by Māori and yet kaumātua are often an untapped resource in the mainstream sector of education. In this thesis the kaumātua and members of the SLT share their experiences of working together and the learning and unlearning that has taken place over a period of four years from 2016 through 2019. They share their vulnerability, humility and strength in the goals they have worked towards over this period of time.

year: 2024