title: Correcting bulk density measurements made with driving hammer equipment

authors: Parfitt, R.L.

subjects: area

abstract: Accurate measurement of dry bulk density is critical for determining stocks of elements such as carbon or nitrogen, in soils. During investigations of changes of soil carbon with time, we resampled soil profiles for bulk density using two methods, namely the driving hammer method and the carving method. The carving method involves gently pressing a metal ring down into a carved pedestal of soil while the hammer method uses percussion to insert a metal ring into the top of a soil layer. We consider the carving method to be more accurate because the soils are less disturbed using carving. The hammer method generally underestimated bulk density by about 5% in comparison with the carving method – depending on soil order and horizon. Most of the bulk density data in the New Zealand National Soils Database (originally collected in moist soils for water release characterisation) were obtained with the hammer method and can now be corrected to the equivalent of data obtained by carving. With data from 44 soil profiles comprising 388 horizons, we showed that a greater correction is needed for soils in the Allophanic (+ 10%) and Melanic soil orders than for other soil orders. The Brown Soils were separated from the remaining soils and a correction factor of about + 9% was required for their A and AB horizons and + 3% for their subsoil horizons. The remaining soils required a correction factor of + 6% for their A and AB horizons and + 3.5% for their subsoil horizons. The correction factor for the A horizons for the Allophanic Soils was similar to their subsoil horizons, suggesting that the influence of aluminium and allophane was overriding that of soil carbon. The Melanic Soils required a correction factor of + 13% for their A horizons but their subsoil horizons responded differently to other soils possibly because of high smectite contents. These differences in bulk density, attributed to change in sampling method, were often greater than changes in soil carbon that would be considered important. Although we used New Zealand soils, we believe that our conclusions will apply to many soils world-wide because most of our soils have equivalents within the FAO and USDA systems of soil classification. This study shows the importance of assessing bulk density methodology, and the possible need for other workers to amend the carbon stocks calculated from the hammer method.

text: Correcting bulk density measurements made with driving hammer equipment Accurate measurement of dry bulk density is critical for determining stocks of elements such as carbon or nitrogen, in soils. During investigations of changes of soil carbon with time, we resampled soil profiles for bulk density using two methods, namely the driving hammer method and the carving method. The carving method involves gently pressing a metal ring down into a carved pedestal of soil while the hammer method uses percussion to insert a metal ring into the top of a soil layer. We consider the carving method to be more accurate because the soils are less disturbed using carving. The hammer method generally underestimated bulk density by about 5% in comparison with the carving method – depending on soil order and horizon. Most of the bulk density data in the New Zealand National Soils Database (originally collected in moist soils for water release characterisation) were obtained with the hammer method and can now be corrected to the equivalent of data obtained by carving. With data from 44 soil profiles comprising 388 horizons, we showed that a greater correction is needed for soils in the Allophanic (+ 10%) and Melanic soil orders than for other soil orders. The Brown Soils were separated from the remaining soils and a correction factor of about + 9% was required for their A and AB horizons and + 3% for their subsoil horizons. The remaining soils required a correction factor of + 6% for their A and AB horizons and + 3.5% for their subsoil horizons. The correction factor for the A horizons for the Allophanic Soils was similar to their subsoil horizons, suggesting that the influence of aluminium and allophane was overriding that of soil carbon. The Melanic Soils required a correction factor of + 13% for their A horizons but their subsoil horizons responded differently to other soils possibly because of high smectite contents. These differences in bulk density, attributed to change in sampling method, were often greater than changes in soil carbon that would be considered important. Although we used New Zealand soils, we believe that our conclusions will apply to many soils world-wide because most of our soils have equivalents within the FAO and USDA systems of soil classification. This study shows the importance of assessing bulk density methodology, and the possible need for other workers to amend the carbon stocks calculated from the hammer method.

year: 2010

title: The effect of tissue flossing on ankle range of motion, jump and sprint performance in elite rugby ‎union athletes

authors: Mills, Blair Stephen

abstract: Context:
Given the relatively novel technique of tissue flossing is currently lacking in the research literature despite some positive findings in preliminary studies, the modality clearly requires further research. Current evidence suggests that band flossing results in performance improvements and may also be an effective method in injury prevention.

Objective:
Previous research has shown that tissue flossing may result in increased ankle ROM, jump and sprinting performance in recreational athletes. The present study aims to extend on this research, within an elite athlete sample.

Design:
counter-balanced, crossover design with experimental and control trials, separated by one week.

Setting:
University laboratory.

Participants:
14 professional male rugby union athletes (mean ± SD: age; 23.9 ± 2.7).

Intervention:
Application of a floss band to both ankles (FLOSS) for two minutes or without flossing of the ankle joints (CON) on two separate occasions.

Main Outcome Measures:
A weight-bearing lunge test (WBLT), a countermovement (CMJ) jump test and a 20m sprint (SPRINT) test pre and at 5 and 30 minutes post application of the floss band or control.

Results:
There were no statistically significant interactions between treatment (FLOSS/CON) and time for any of the measured variables (p > 0.05). Effect size analysis revealed small benefits for FLOSS in comparison to CON for CMJ performance 5 mins post (d = 0.28) and for 10m (d = -0.45) and 15m (d = -0.24) sprint time 30 mins post.

Conclusion:
Findings from the current study suggest minimal benefits of tissue flossing when applied to the ankle joint in elite athletes for up to 30 minutes following their application.

text: The effect of tissue flossing on ankle range of motion, jump and sprint performance in elite rugby ‎union athletes Context:
Given the relatively novel technique of tissue flossing is currently lacking in the research literature despite some positive findings in preliminary studies, the modality clearly requires further research. Current evidence suggests that band flossing results in performance improvements and may also be an effective method in injury prevention.

Objective:
Previous research has shown that tissue flossing may result in increased ankle ROM, jump and sprinting performance in recreational athletes. The present study aims to extend on this research, within an elite athlete sample.

Design:
counter-balanced, crossover design with experimental and control trials, separated by one week.

Setting:
University laboratory.

Participants:
14 professional male rugby union athletes (mean ± SD: age; 23.9 ± 2.7).

Intervention:
Application of a floss band to both ankles (FLOSS) for two minutes or without flossing of the ankle joints (CON) on two separate occasions.

Main Outcome Measures:
A weight-bearing lunge test (WBLT), a countermovement (CMJ) jump test and a 20m sprint (SPRINT) test pre and at 5 and 30 minutes post application of the floss band or control.

Results:
There were no statistically significant interactions between treatment (FLOSS/CON) and time for any of the measured variables (p > 0.05). Effect size analysis revealed small benefits for FLOSS in comparison to CON for CMJ performance 5 mins post (d = 0.28) and for 10m (d = -0.45) and 15m (d = -0.24) sprint time 30 mins post.

Conclusion:
Findings from the current study suggest minimal benefits of tissue flossing when applied to the ankle joint in elite athletes for up to 30 minutes following their application.

year: 2019

title: Māori and kava: New drug fashion or re-engagement with 'kawa'?

authors: Aporosa, S. 'Apo'

subjects: kava

abstract: The Pacific “cultural keystone species” (Garibaldi & Turner, 2004, pp.1,5) kava is uniquely linked with notions of mana (spiritual power) and used to infuse efficacy into celebrations and life events. The drink, made from this potent icon of identity, brings on feelings of relaxation without marked euphoria, aiding clear-minded talanoa (discussion) to facilitate important and/or contentious dialogue. The sharing and drinking of kava as part of host/guest formalities is used in bringing about mutuality and unity (Aporosa, 2019). It is estimated there are more than 20,000 kava users in Aotearoa/New Zealand on an average Friday or Saturday night, with increasing interest and uptake of this indigenous drink by Māori. Crowley (1994) reports that the Māori word ‘kawa’, literally meaning ‘marae protocol’, has its linguistic foundations in ‘kava’ and the practices associated with this cultural keystone species. This paper explores that linguistic union to ask whether increased kava use by Māori has greater significance than simply a new interaction with a foreign drug substance. Further, due to the use of kava in facilitating talanoa (discussion), the possibility of kava playing a similar role for Māori is considered, one linked to ancestral Pacific connections aimed at assisting kōrero (talanoa), cultural connectedness and practice.

text: Māori and kava: New drug fashion or re-engagement with 'kawa'? The Pacific “cultural keystone species” (Garibaldi & Turner, 2004, pp.1,5) kava is uniquely linked with notions of mana (spiritual power) and used to infuse efficacy into celebrations and life events. The drink, made from this potent icon of identity, brings on feelings of relaxation without marked euphoria, aiding clear-minded talanoa (discussion) to facilitate important and/or contentious dialogue. The sharing and drinking of kava as part of host/guest formalities is used in bringing about mutuality and unity (Aporosa, 2019). It is estimated there are more than 20,000 kava users in Aotearoa/New Zealand on an average Friday or Saturday night, with increasing interest and uptake of this indigenous drink by Māori. Crowley (1994) reports that the Māori word ‘kawa’, literally meaning ‘marae protocol’, has its linguistic foundations in ‘kava’ and the practices associated with this cultural keystone species. This paper explores that linguistic union to ask whether increased kava use by Māori has greater significance than simply a new interaction with a foreign drug substance. Further, due to the use of kava in facilitating talanoa (discussion), the possibility of kava playing a similar role for Māori is considered, one linked to ancestral Pacific connections aimed at assisting kōrero (talanoa), cultural connectedness and practice.

year: 2019