title: Finding synaptic couplings from a biophysical model of motor evoked potentials after theta-burst transcranial magnetic stimulation

authors: Wilson, Marcus T.

subjects: Cortical plasticity

abstract: OBJECTIVE: We aimed to use measured input-output (IO) data to identify the best fitting model for motor evoked potentials. METHODS: We analyzed existing IO data before and after intermittent and continuous theta-burst stimulation (iTBS & cTBS) from a small group of subjects (18 for each). We fitted individual synaptic couplings and sensitivity parameters using variations of a biophysical model. A best performing model was selected and analyzed. RESULTS: cTBS gives a broad reduction in MEPs for amplitudes larger than resting motor threshold (RMT). Close to threshold, iTBS gives strong potentiation. The model captures individual IO curves. There is no change to the population average synaptic weights post TBS but the change in excitatory-to-excitatory synaptic coupling is strongly correlated with the experimental post-TBS response relative to baseline. CONCLUSIONS: The model describes population-averaged and individual IO curves, and their post-TBS change. Variation among individuals is accounted for with variation in synaptic couplings, and variation in sensitivity of neural response to stimulation. SIGNIFICANCE: The best fitting model could be applied more broadly and validation studies could elucidate underlying biophysical meaning of parameters.

text: Finding synaptic couplings from a biophysical model of motor evoked potentials after theta-burst transcranial magnetic stimulation OBJECTIVE: We aimed to use measured input-output (IO) data to identify the best fitting model for motor evoked potentials. METHODS: We analyzed existing IO data before and after intermittent and continuous theta-burst stimulation (iTBS & cTBS) from a small group of subjects (18 for each). We fitted individual synaptic couplings and sensitivity parameters using variations of a biophysical model. A best performing model was selected and analyzed. RESULTS: cTBS gives a broad reduction in MEPs for amplitudes larger than resting motor threshold (RMT). Close to threshold, iTBS gives strong potentiation. The model captures individual IO curves. There is no change to the population average synaptic weights post TBS but the change in excitatory-to-excitatory synaptic coupling is strongly correlated with the experimental post-TBS response relative to baseline. CONCLUSIONS: The model describes population-averaged and individual IO curves, and their post-TBS change. Variation among individuals is accounted for with variation in synaptic couplings, and variation in sensitivity of neural response to stimulation. SIGNIFICANCE: The best fitting model could be applied more broadly and validation studies could elucidate underlying biophysical meaning of parameters.

year: 2023-02-15

title: A review on treatment processes of chicken manure

authors: Manogaran, M. Devendran

abstract: The poultry industry is a fast-growing industry fuelled by overwhelming customer demand. Of the different poultry meat options, chicken is arguably the most popular as it is the second most staple food item in Malaysia after rice. Consequently, due to the overwhelming demand for chicken meat, chicken manure is produced in abundance. In fact, a chicken produces 80 g to 100 g of manure daily, corresponding to 3-4% of its body weight. Utilizing the raw manure as an organic fertilizer without any prior treatment results in adverse environmental consequences as this common practice acts as a vector for propagation of pathogens, attracting flies and pests as well as contributing to odour problems. Treatment methods using pesticides, effective microorganisms and daily collection and disposal have been adopted by the farmers but these techniques are relatively costly and associated with potential environmental threats. Other techniques such as composting, pyrolysis, gasification, anaerobic digestion, hydrothermal liquefaction and torrefaction are drawing interest due to their ability to convert waste to value-added products. Approximately, 77,209 tonnes of chicken manure produced per day in Malaysia in 2014 can potentially generate up to 3.86 million m3 of methane from anaerobic digestion, equivalent to potential generation of 139.5 TJ of heat or 38.7 GWh of electricity theoretically. This paper reviews the technical and practical aspects of the techniques mentioned above in terms of operation, performance and limitations. This paper also examines the preferential treatment techniques in relation to the product outputs with good market potential while being environmentally sustainable.

text: A review on treatment processes of chicken manure The poultry industry is a fast-growing industry fuelled by overwhelming customer demand. Of the different poultry meat options, chicken is arguably the most popular as it is the second most staple food item in Malaysia after rice. Consequently, due to the overwhelming demand for chicken meat, chicken manure is produced in abundance. In fact, a chicken produces 80 g to 100 g of manure daily, corresponding to 3-4% of its body weight. Utilizing the raw manure as an organic fertilizer without any prior treatment results in adverse environmental consequences as this common practice acts as a vector for propagation of pathogens, attracting flies and pests as well as contributing to odour problems. Treatment methods using pesticides, effective microorganisms and daily collection and disposal have been adopted by the farmers but these techniques are relatively costly and associated with potential environmental threats. Other techniques such as composting, pyrolysis, gasification, anaerobic digestion, hydrothermal liquefaction and torrefaction are drawing interest due to their ability to convert waste to value-added products. Approximately, 77,209 tonnes of chicken manure produced per day in Malaysia in 2014 can potentially generate up to 3.86 million m3 of methane from anaerobic digestion, equivalent to potential generation of 139.5 TJ of heat or 38.7 GWh of electricity theoretically. This paper reviews the technical and practical aspects of the techniques mentioned above in terms of operation, performance and limitations. This paper also examines the preferential treatment techniques in relation to the product outputs with good market potential while being environmentally sustainable.

year: 2022

title: A path to lotions and potions: Ngāti te Maunga ahi kā use of rongoā for hapū wellbeing

authors: Diamond, Kiri

subjects: rongoā

abstract: The research aimed to determine the challenges and improvements required during the implementation of the rongoā programme. The rongoā programme was based on a papakāinga near a marae, in a semi-rural location with difficult access. Participatory action research and autoethnography methods were used with the ahi kā (local residence) to develop a programme that would fulfil the hapū ora (extended family wellbeing) goals.  The goals of the programme were: for the ahi kā to use rongoā (modalities of health) confidently for their wellbeing; consistently use a Facebook page to learn and share information and to develop a database of the local rongoā rākau (medicinal plant). The ahi kā identified a further question to ask Facebook members to understand what motivated their participation and a survey was conducted. The ahi kā also wanted to understand the local doctor’s view on rongoā and its context on health provision in their area. An interview was conducted and the survey and interview added to the understanding of what the ahi kā could do to improve theirs and the hapū whānau (group extended family) wellbeing.
The findings of the research highlighted the complexities that arise from conducting research in a bicultural space where a common understanding of cultural knowledge is assumed to be homogenous. A shared history with colonisation and religious beliefs brought to the forefront the multiplicity Māori work through to determine a shared hapū identity. Based on an understanding of Māori principle values and tikanga (ways of enacting values), as understood by ahi kā, transformed a programme of learning how to make lotions and potions for the ahi kā, into influencing hapū members to change their attitudes and behaviours to their environment and their wellbeing.
This research highlighted the role that ahi kā hold as keepers of cultural knowledge that is rooted in the papakāinga through ancestral links that informs the identity of a hapū. Learning how to use rongoā provided ahi kā a platform to learn a new skill while helping the hapū heal through connecting with the identity and land of the hapū they belong to.

text: A path to lotions and potions: Ngāti te Maunga ahi kā use of rongoā for hapū wellbeing The research aimed to determine the challenges and improvements required during the implementation of the rongoā programme. The rongoā programme was based on a papakāinga near a marae, in a semi-rural location with difficult access. Participatory action research and autoethnography methods were used with the ahi kā (local residence) to develop a programme that would fulfil the hapū ora (extended family wellbeing) goals.  The goals of the programme were: for the ahi kā to use rongoā (modalities of health) confidently for their wellbeing; consistently use a Facebook page to learn and share information and to develop a database of the local rongoā rākau (medicinal plant). The ahi kā identified a further question to ask Facebook members to understand what motivated their participation and a survey was conducted. The ahi kā also wanted to understand the local doctor’s view on rongoā and its context on health provision in their area. An interview was conducted and the survey and interview added to the understanding of what the ahi kā could do to improve theirs and the hapū whānau (group extended family) wellbeing.
The findings of the research highlighted the complexities that arise from conducting research in a bicultural space where a common understanding of cultural knowledge is assumed to be homogenous. A shared history with colonisation and religious beliefs brought to the forefront the multiplicity Māori work through to determine a shared hapū identity. Based on an understanding of Māori principle values and tikanga (ways of enacting values), as understood by ahi kā, transformed a programme of learning how to make lotions and potions for the ahi kā, into influencing hapū members to change their attitudes and behaviours to their environment and their wellbeing.
This research highlighted the role that ahi kā hold as keepers of cultural knowledge that is rooted in the papakāinga through ancestral links that informs the identity of a hapū. Learning how to use rongoā provided ahi kā a platform to learn a new skill while helping the hapū heal through connecting with the identity and land of the hapū they belong to.

year: 2019