title: Canine accuracy in the scent detection and discrimination of invasive fish

authors: Seal, Laura Claire

abstract: The scent-detection accuracy of dogs (Canis familiaris) was assessed as they learned to discriminate between water samples from aquaria containing koi carp (Cyprinus carpio), goldfish (Carassius auratus) or no fish, at systematically diluted concentrations. The study was conducted using an automated apparatus. Three dogs were trained in a go/no-go task where hits on target (koi carp) samples were reinforced and correct rejections of non-target (goldfish and no-fish) samples had no programmed consequences. Conducting a control test indicated that the dogs’ accuracy measures were likely influenced by extraneous variables. Consequently, modifications were made to procedures and the apparatus. A multiple-probe design experiment found the dogs were able to detect koi carp scent at all of the concentrations tested (from 0.098 mL/100 mL to 0.00094 mL/100 mL), equivalent to an effective biomass range of between 72.5 and 0.4 kg/ha. No clear relationship between accuracy measures and the systematic dilution of the sample concentration was observed for any of the dogs. A test of the dogs’ accuracy with the samples removed from the apparatus suggested that volatiles evaporating from the sampled aquarium water may have been accumulating in the segments as the dogs continued to respond according to the status of the samples that were previously in each segment. Sensitivity was found to be similar across first trials and second trials for target samples. Specificity was found to increase for non-target samples from first trials to second trials. These results have significant practical implications for the use of scent-detection dogs for koi carp detection and the further development of research methods for their training and assessment.

text: Canine accuracy in the scent detection and discrimination of invasive fish The scent-detection accuracy of dogs (Canis familiaris) was assessed as they learned to discriminate between water samples from aquaria containing koi carp (Cyprinus carpio), goldfish (Carassius auratus) or no fish, at systematically diluted concentrations. The study was conducted using an automated apparatus. Three dogs were trained in a go/no-go task where hits on target (koi carp) samples were reinforced and correct rejections of non-target (goldfish and no-fish) samples had no programmed consequences. Conducting a control test indicated that the dogs’ accuracy measures were likely influenced by extraneous variables. Consequently, modifications were made to procedures and the apparatus. A multiple-probe design experiment found the dogs were able to detect koi carp scent at all of the concentrations tested (from 0.098 mL/100 mL to 0.00094 mL/100 mL), equivalent to an effective biomass range of between 72.5 and 0.4 kg/ha. No clear relationship between accuracy measures and the systematic dilution of the sample concentration was observed for any of the dogs. A test of the dogs’ accuracy with the samples removed from the apparatus suggested that volatiles evaporating from the sampled aquarium water may have been accumulating in the segments as the dogs continued to respond according to the status of the samples that were previously in each segment. Sensitivity was found to be similar across first trials and second trials for target samples. Specificity was found to increase for non-target samples from first trials to second trials. These results have significant practical implications for the use of scent-detection dogs for koi carp detection and the further development of research methods for their training and assessment.

year: 2019

title: Regular versus diffusive photospheric flux cancellation

authors: Litvinenko, Yuri E.

subjects: magnetic fields

abstract: Observations of photospheric flux cancellation on the Sun imply that cancellation can be a diffusive rather than regular process. A criterion is derived, which quantifies the parameter range in which diffusive photospheric cancellation should occur. Numerical estimates show that regular cancellation models should be expected to give a quantitatively accurate description of photospheric cancellation. The estimates rely on a recently suggested scaling for a turbulent magnetic diffusivity, which is consistent with the diffusivity measurements on spatial scales varying by almost two orders of magnitude. Application of the turbulent diffusivity to large-scale dispersal of the photospheric magnetic flux is discussed.

text: Regular versus diffusive photospheric flux cancellation Observations of photospheric flux cancellation on the Sun imply that cancellation can be a diffusive rather than regular process. A criterion is derived, which quantifies the parameter range in which diffusive photospheric cancellation should occur. Numerical estimates show that regular cancellation models should be expected to give a quantitatively accurate description of photospheric cancellation. The estimates rely on a recently suggested scaling for a turbulent magnetic diffusivity, which is consistent with the diffusivity measurements on spatial scales varying by almost two orders of magnitude. Application of the turbulent diffusivity to large-scale dispersal of the photospheric magnetic flux is discussed.

year: 2011

title: Military Settlement in the Middle Waikato Basin

authors: Allen, Peter D.H.

abstract: Military settlement formed a brief but distinctive phase in the European occupation of the Middle Waikato Basin. Prior to the 1863 - 1864 Waikato War, few Europeans, other than a small number of missionaries and traders, were settled in the region. The setting of the Middle Waikato Basin was largely unmodified by Man, except along the major rivers where a dense Maori population was settled. 
During the 1850's, the encroachment of European settlers upon Maori tribal lands in many North Island regions, including the Waikato, led to an increase in tension between the two populations and open conflict. This conflict slowed down the progress of colonization in the North Island. To enable colonization to continue in those regions disturbed by Maori unrest, a scheme of military settlement was devised. The aim of this scheme was the formation of compact, self-sufficient defensive settlements to act as a deterrent to Maori unrest. These settlements would also provide an assurance to settlers of security for their life and property.
 Military settlement in the Middle Waikato Basin consisted of two phases. In the first phase, the nodal points of the military settlements, the townships, were established and occupied by the military settlers. In the second phase, farm districts were surveyed around the nodal points and the military settlers moved out from the townships to occupy and develop the land they were allocated. A number of factors, relating to deficiencies in the scheme of military settlement and to the particular problems of settlement in the region, contributed to the failure of the military settlers to successfully establish farms on the land they were allocated. 
The scheme of military settlement largely failed as a method of colonization in the Middle Waikato Basin. However, the pattern of human occupation, established in the initial phase of military settlement, remained when the need for defensive settlements had gone, and forms the basis of the present pattern of settlement.

text: Military Settlement in the Middle Waikato Basin Military settlement formed a brief but distinctive phase in the European occupation of the Middle Waikato Basin. Prior to the 1863 - 1864 Waikato War, few Europeans, other than a small number of missionaries and traders, were settled in the region. The setting of the Middle Waikato Basin was largely unmodified by Man, except along the major rivers where a dense Maori population was settled. 
During the 1850's, the encroachment of European settlers upon Maori tribal lands in many North Island regions, including the Waikato, led to an increase in tension between the two populations and open conflict. This conflict slowed down the progress of colonization in the North Island. To enable colonization to continue in those regions disturbed by Maori unrest, a scheme of military settlement was devised. The aim of this scheme was the formation of compact, self-sufficient defensive settlements to act as a deterrent to Maori unrest. These settlements would also provide an assurance to settlers of security for their life and property.
 Military settlement in the Middle Waikato Basin consisted of two phases. In the first phase, the nodal points of the military settlements, the townships, were established and occupied by the military settlers. In the second phase, farm districts were surveyed around the nodal points and the military settlers moved out from the townships to occupy and develop the land they were allocated. A number of factors, relating to deficiencies in the scheme of military settlement and to the particular problems of settlement in the region, contributed to the failure of the military settlers to successfully establish farms on the land they were allocated. 
The scheme of military settlement largely failed as a method of colonization in the Middle Waikato Basin. However, the pattern of human occupation, established in the initial phase of military settlement, remained when the need for defensive settlements had gone, and forms the basis of the present pattern of settlement.

year: 1969