title: Exploring cross-modal association in canine (canis familiaris) scent detection: A framework for training dogs to identify multiple odours

authors: Campbell-Smith, Felicity

subjects: canine scent detection

abstract: Dog’s olfaction abilities and trainability have made them valuable companions in scent detection tasks for centuries. While research has focused on dogs detecting single odours, there is a gap in understanding if they can emit different responses to different odours. Based on the principles of stimulus control and existing evidence of dogs’ ability to learn to perform similar tasks, it was hypothesised that dogs, using cross-modal association through olfaction and vision modalities, can match odours to corresponding shapes. Using an automated scent delivery apparatus, four dogs were trained using operant conditioning procedures to discriminate between two odours and select a corresponding shape. One dog met the mastery criteria and progressed to three odours. It was found that dogs were able to discriminate between odours at greater accuracy than chance, confirming our hypothesis. Yet, all dogs did display a bias towards one of the four touchscreen quadrants. The findings were similar to those observed in other studies involving different animal species, but the accuracy rates observed in this study were lower than those reported in other similar studies. These findings have implications for tasks the detection of multiple scents and further the understanding of dogs’ abilities to perform cross-modal discrimination tasks. This study established a methodological framework for cross-modal scent discrimination tasks but there are several improvements to the methods that might enhance dogs’ performance in future research.

text: Exploring cross-modal association in canine (canis familiaris) scent detection: A framework for training dogs to identify multiple odours Dog’s olfaction abilities and trainability have made them valuable companions in scent detection tasks for centuries. While research has focused on dogs detecting single odours, there is a gap in understanding if they can emit different responses to different odours. Based on the principles of stimulus control and existing evidence of dogs’ ability to learn to perform similar tasks, it was hypothesised that dogs, using cross-modal association through olfaction and vision modalities, can match odours to corresponding shapes. Using an automated scent delivery apparatus, four dogs were trained using operant conditioning procedures to discriminate between two odours and select a corresponding shape. One dog met the mastery criteria and progressed to three odours. It was found that dogs were able to discriminate between odours at greater accuracy than chance, confirming our hypothesis. Yet, all dogs did display a bias towards one of the four touchscreen quadrants. The findings were similar to those observed in other studies involving different animal species, but the accuracy rates observed in this study were lower than those reported in other similar studies. These findings have implications for tasks the detection of multiple scents and further the understanding of dogs’ abilities to perform cross-modal discrimination tasks. This study established a methodological framework for cross-modal scent discrimination tasks but there are several improvements to the methods that might enhance dogs’ performance in future research.

year: 2024-04-19

title: Photodegradation leads to increased carbon dioxide losses from terrestrial organic matter

authors: Rutledge, Susanna

subjects: abiotic decomposition

abstract: CO₂ production in terrestrial ecosystems is generally assumed to be solely biologically driven while the role of abiotic processes has been largely overlooked. In addition to microbial decomposition, photodegradation – the direct breakdown of organic matter (OM) by solar irradiance – has been found to contribute to litter mass loss in dry ecosystems. Previous small-scale studies have shown that litter degradation by irradiance is accompanied by emissions of CO₂. However, the contribution of photodegradation to total CO₂ losses at ecosystems scales is unknown. This study determined the proportion of the total CO₂ losses caused by photodegradation in two ecosystems: a bare peatland in New Zealand and a seasonally dry grassland in California. The direct effect of solar irradiance on CO₂  production was examined by comparing daytime CO₂  fluxes measured using eddy covariance (EC) systems with simultaneous measurements made using an opaque chamber and the soil CO₂ gradient technique, and with night-time EC measurements under the same soil temperature and moisture conditions. In addition, a transparent chamber was used to directly measure CO₂ fluxes from OM caused by solar irradiance. Photodegradation contributed 19% of the annual CO₂ flux from the peatland and almost 60% of the dry season CO₂ flux from the grassland, and up to 62% and 92% of the summer mid-day CO₂ fluxes, respectively. Our results suggest that photodegradation may be important in a wide range of ecosystems with exposed OM. Furthermore, the practice of partitioning daytime ecosystem CO₂ exchange into its gross components by assuming that total daytime CO₂ losses can be approximated using estimates of biological respiration alone may be in error. To obtain robust estimates of global ecosystem–atmosphere carbon transfers, the contribution of photodegradation to OM decomposition must be quantified for other ecosystems and the results incorporated into coupled carbon–climate models.

text: Photodegradation leads to increased carbon dioxide losses from terrestrial organic matter CO₂ production in terrestrial ecosystems is generally assumed to be solely biologically driven while the role of abiotic processes has been largely overlooked. In addition to microbial decomposition, photodegradation – the direct breakdown of organic matter (OM) by solar irradiance – has been found to contribute to litter mass loss in dry ecosystems. Previous small-scale studies have shown that litter degradation by irradiance is accompanied by emissions of CO₂. However, the contribution of photodegradation to total CO₂ losses at ecosystems scales is unknown. This study determined the proportion of the total CO₂ losses caused by photodegradation in two ecosystems: a bare peatland in New Zealand and a seasonally dry grassland in California. The direct effect of solar irradiance on CO₂  production was examined by comparing daytime CO₂  fluxes measured using eddy covariance (EC) systems with simultaneous measurements made using an opaque chamber and the soil CO₂ gradient technique, and with night-time EC measurements under the same soil temperature and moisture conditions. In addition, a transparent chamber was used to directly measure CO₂ fluxes from OM caused by solar irradiance. Photodegradation contributed 19% of the annual CO₂ flux from the peatland and almost 60% of the dry season CO₂ flux from the grassland, and up to 62% and 92% of the summer mid-day CO₂ fluxes, respectively. Our results suggest that photodegradation may be important in a wide range of ecosystems with exposed OM. Furthermore, the practice of partitioning daytime ecosystem CO₂ exchange into its gross components by assuming that total daytime CO₂ losses can be approximated using estimates of biological respiration alone may be in error. To obtain robust estimates of global ecosystem–atmosphere carbon transfers, the contribution of photodegradation to OM decomposition must be quantified for other ecosystems and the results incorporated into coupled carbon–climate models.

year: 2009

title: What is the difference? What factors contribute to the variation of achievement for Year 7 and 8 Māori students in high decile, full primary schools?

authors: McLocklan, Sue

subjects: Maori student achievement

abstract: The educational disparity between indigenous Māori students and those of the majority continue to be a major issue in New Zealand. Attempting to bridge the gap for Māori students has generated focus on Māori student engagement in the classroom, the actions and understanding of the teacher and the relationship and interactions between the teacher and students in their learning environment. Elements of culturally responsive pedagogy have been identified as positive contributing factors to accelerating academic achievement for secondary Māori mainstream students. 
This small-scale cross-cultural exploratory qualitative research project seeks to identify the factors that contribute to student achievement variation for Year 7 and 8 students in high decile full primary schools and the integration of teacher’s cultural competencies in high quality learning opportunities. Within a kaupapa Māori research process, this study uses empirical data collected from a purposive sample through a semi-structured individual interview and a for self-assessment. Voluntary research participants were twelve students and six teachers in three schools in the Bay of Plenty, Waikato and Wellington regions. This research examines the engagement of student and teacher in pedagogical practice, learning variables, cultural knowledge and practices attributable to positive academic achievement for Māori. 
The findings reveal that when teachers place themselves in an agentic position; adopt a professional commitment and willingness to engage in effective relations, interactions and reciprocal practices to support Māori learners, high levels of relational trust and expectations prevail through mutual respect and interdependence to attain successful educational outcomes.
Further teacher professional learning is essential to enlighten and deepen teachers' understanding of culturally responsive pedagogy to enable Māori learners to reach their potential to participate and contribute in their world of choice.

text: What is the difference? What factors contribute to the variation of achievement for Year 7 and 8 Māori students in high decile, full primary schools? The educational disparity between indigenous Māori students and those of the majority continue to be a major issue in New Zealand. Attempting to bridge the gap for Māori students has generated focus on Māori student engagement in the classroom, the actions and understanding of the teacher and the relationship and interactions between the teacher and students in their learning environment. Elements of culturally responsive pedagogy have been identified as positive contributing factors to accelerating academic achievement for secondary Māori mainstream students. 
This small-scale cross-cultural exploratory qualitative research project seeks to identify the factors that contribute to student achievement variation for Year 7 and 8 students in high decile full primary schools and the integration of teacher’s cultural competencies in high quality learning opportunities. Within a kaupapa Māori research process, this study uses empirical data collected from a purposive sample through a semi-structured individual interview and a for self-assessment. Voluntary research participants were twelve students and six teachers in three schools in the Bay of Plenty, Waikato and Wellington regions. This research examines the engagement of student and teacher in pedagogical practice, learning variables, cultural knowledge and practices attributable to positive academic achievement for Māori. 
The findings reveal that when teachers place themselves in an agentic position; adopt a professional commitment and willingness to engage in effective relations, interactions and reciprocal practices to support Māori learners, high levels of relational trust and expectations prevail through mutual respect and interdependence to attain successful educational outcomes.
Further teacher professional learning is essential to enlighten and deepen teachers' understanding of culturally responsive pedagogy to enable Māori learners to reach their potential to participate and contribute in their world of choice.

year: 2013