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Could machine learning predict meat quality traits using the metabolic fingerprints of lamb meat analysed with REIMS?
No full textHigh pH is a quality defect in meat and is often a result of pre-slaughter stress. We have developed a farmyard stress model that is a useful tool for research on high ultimate pH meat [1]. In this study, we used Rapid Evaporative Ionisation Mass Spectrometry (REIMS) to fingerprint the metabolites within the meat [2]. REIMS data was able to distinguish between muscles of lambs that have been exercised pre-slaughter compared to those who have not [2]. Most REIMS data analysis is done using multivariate statistics. These methods are powerful but lack inbuilt methods to refine the REIMS dataset to focus on only those variables that are important for explaining the phenomenon of interest. This is critical for methods such as REIMS where most of the data collected is irrelevant to the study question and interferes with model validity. Iterative PLS-DA and machine learning have been used for REIMS analysis but their application has been limited to date.
Machine learning (ML) is a novel and emerging tool incorporating artificial intelligence to train the model to predict the output with algorithm input. The potential of advanced machine learning compared to conventional multivariate statistical analysis has been shown in classifying beef cuts from images, fish speciation based on REIMS features and determining chicken freshness via colorimetric sensor array. The current study evaluated using WEKA and Tensorflow platforms to predict ultimate pH and meat quality parameters from the REIMS metabolic fingerprint. These data will contribute towards defining and designing much larger experiments run in commercial processing plants to develop rapid screening systems to predict future pH as meat is processed
Allowing for refraction in back propagation
No full textThis paper shows that when using position biased antenna measurements of a phantom object, allowing for refraction can improve the reconstructed image. We use a modified version of the "back propagation"(or zero order Born approximation) algorithm to allow for refraction, geometric ray convergence and material effects
Environmental regulation and energy efficiency: Empirical evidence from the low-carbon city pilot program in China
No full textImprovements in energy efficiency will be instrumental in meeting China’s ambitious emission targets while providing adequate energy to support the country’s rising living standards. We investigate whether the low-carbon city pilot (LCCP) program has improved energy efficiency in participating cities. To this end, we analyze prefecture-level data in 249 cities between 2004 and 2016 using the difference-in-differences approach. The findings reveal that the program significantly improved the energy efficiency of pilot cities by promoting technological innovation and restructuring the cities’ industry mix. The positive impacts of the LCCP program on energy efficiency were more pronounced in cities in China’s eastern region and areas lacking natural resources. Furthermore, the program was more effective in cities with high energy consumption and per capita income on the one hand and low foreign direct investment and sulfur dioxide emissions on the other
Three essays on CEO expertise power and bank strategic decisions : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
Get PDFA CEO's expertise power is a combination of a CEO’s educational background, career path and experience, which influences the critical components of the bank task environment, e.g., bank diversification, bank lending and other financial services, thus, needing a close attention to investigate the CEO’s expertise power and bank key decisions. This thesis comprises three essays on a chief executive officer’s (CEO’s) expertise power and bank strategic decisions using US commercial banks data from 1990-2020. The first essay examines the effect of a CEO’s expertise power on bank diversification. The results show that a CEO's expertise power is positively associated with bank diversification. Market competition and board composition (size and independence) positively moderate this relationship. The results also show that CEO delta and vega are the underlying mechanisms through which expertise power leads to higher diversification. I address endogeneity concerns using the two-stage least squares, Heckman estimation and the Differences-in-Differences approaches and check robustness in several ways.
The second essay examines the effect of a CEO’s expertise power on bank lending growth. The result reveals that a CEO's expertise power is positively associated with bank loan growth. Further, the result shows that GDP growth, board size and gender diversity positively and financial crises negatively affect this relationship. In channel analyses, I find that bank opacity (information asymmetry) and CEO delta (CEO pay-performance sensitivity) are the underlying mechanisms through which the CEO’s expertise power is associated with loan growth. I address endogeneity concerns using the fixed effects, generalized method of moments (GMM) and Heckman's two-stage approaches.
The third and final essay examines the effect of CEO expertise power on bank tax avoidance. The result shows that a CEO's expertise power is positively associated with bank tax avoidance. The result also finds that diversification and gender diversity negatively and board size and financial crises positively affect this relationship. In channel analyses, the result reveals that CEO delta and vega are the underlying mechanisms through which the CEO’s expertise power is associated with bank tax avoidance. I address endogeneity concerns using the fixed effects, generalized method of moments (GMM), Differences-in-Differences (DID) and Heckman's two-stage approaches.
This study enhances the scope of upper echelon theory by examining the implications of CEO characteristics (expertise power) for bank diversification, loan growth and tax avoidance decisions. This study provides a new explanation for bank diversification, loan growth and tax avoidance that will be useful for policymakers in developing bank strategy for CEO appointment that affects bank decisions.
This study has several managerial and practical implications. The findings show that expert CEOs are highly skilled managers who can efficiently manage bank risk and other challenges, such as financial crises, reduce bank information asymmetry that improves bank lending, improve bank risk management and performance that generate more cash flows. Thus, CEO expertise contributes to bank stability by making value enhancing decisions
Development of an integrated strategy to manage Sclerotinia sclerotiorum : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
No full textSclerotinia sclerotiorum is a ubiquitous, necrotic fungus with a broad host range and as a plant pathogen infects a wide range of plants in New Zealand, including many economically important crops. Managing S. sclerotiorum by a single management practice is challenging due to the naturally high pathogenicity and the production of survival structures (sclerotia) in the soil. Hence, the aim of this study was to investigate the potential of combined applications of biofumigation, Perlka® and the biocontrol agent, Coniothyrium minitans, for controlling S. sclerotiorum.
In the in vitro experiments done to test the effect of medium and cold preconditioning on carpogenic germination of sclerotia and development of apothecia, it was observed that carpogenic germination of sclerotia and the total number of apothecia per Petri plate was greater in water agar compared to potting mix and sand. Comparatively, the differentiation of apothecia was greater in potting mix and faster in sand. The isolates which originated from the Auckland region (LUPP2650, LUPP2651 and LUPP2662) showed greater carpogenic germination and development of apothecia compared to those originating from Canterbury (LUPP469, LUPP480, LUPP483, LUPP462) under the in vitro conditions used in this study. A few isolates (LUPP479, LUPP480, LUPP2660) showed a positive response for cold preconditioning (at 4°C) in terms of germination of sclerotia (%) and/or time to develop the first apothecium.
The in vitro assessment showed that Brassica juncea ‘Caliente 199’ has greater potential to inhibit the mycelial growth of 10 isolates of S. sclerotium (60%) compared to the other tested biofumigant crops, Eruca sativa ‘Nemat’ (rocket) (29%), Brassica juncea ‘Unknown’ (brown mustard) (10%) and Sinapis alba ‘SKU 4295’ (white mustard) (7%). Plant tissue of ‘Caliente 199’ harvested at 50% or 100% flowering and adjusted to 80% (w/w) moisture resulted in greater mycelial inhibition compared with the vegetative tissue. High quantities of plant tissue of ‘Caliente 199’ of 5 g and 10 g resulted in greater mycelial inhibition than lower quantities. The EC50 of the S. sclerotium isolates LUPP475 and LUPP2650 was 3.76 g and 3.23 g, respectively. Using whole plant tissue (shoots + roots) and only shoot tissue resulted in a similar inhibition of the mycelial growth in all four isolates tested. The S. sclerotiorum isolate LUPP475 showed more tolerance to biofumigation with ‘Caliente 199’ compared to LUPP2650 in terms of mycelial inhibition.
Using the plant tissue of ‘Caliente 199’ at 50% or 100% flowering and adjusting to 80% (w/w) moisture at the higher quantities (10 g) resulted in the maximum inhibition of mycelial germination of sclerotia of four S. sclerotiorum isolates. Whole plant tissues showed better inhibition of mycelial germination of sclerotia than only shoots. S. sclerotiorum isolates LUPP475 and LUPP2650 indicated a fungistatic effect on mycelial germination of sclerotia by ‘Caliente 199’ but isolates LUPP458 and LUPP463 germinated rapidly even after exposure to 10 g of whole plant tissues. Using ‘Caliente 199’ equivalent to the field rates of 75 t/ha and 100 t/ha inhibited the carpogenic germination of sclerotia by ~46% compared to the control but failed to reduce the sclerotial viability.
In the box bioassays, using Perlka® alone, equivalent to the field rate of 400 kg/ha, resulted in complete inhibition of carpogenic germination although sclerotial viability was not reduced. Applying C. minitans resulted in complete inhibition of carpogenic germination and significant sclerotial mortality (95.0%). Applying C. minitans in combined application with Perlka® also resulted in 100% suppression of carpogenic germination and greater sclerotial mortality (97.5%). A synergistic effect of the combined application on carpogenic germination of S. sclerotiorum sclerotia was not observed, and sclerotial mortality was indicated to be predominantly due to the antagonistic effect of C. minitans.
Under glasshouse conditions, applying C. minitans in the combined treatment with biofumigation resulted in significant suppression of apothecial development and Sclerotinia disease of lettuce. Applying Perlka® also provided a significant reduction of apothecial development and effective control of Sclerotinia disease of lettuce. Biofumigation alone failed to provide substantial control of either apothecial development or Sclerotinia disease of lettuce.
The biological control of S. sclerotiorum using C. minitans can be recommended as a vital component in an integrated pest management (IPM) programme. Also, Perlka® provided effective control of S. sclerotiorum and proved to be a compatible component in an IPM approach. It is recommended to allow at least 6-8 weeks between C. minitans treatment and planting biofumigant plants because of the greater sensitivity of C. minitans to the volatile bioactive compounds and to allow the antagonist to colonise the sclerotia. Leaving 7-14 days between the Perlka® pretreatment and sowing biofumigant seeds (Brassica spp.) is also recommended to avoid the possible phototoxic effect of Perlka®. The results of this study will aid in the development of an IPM strategy to achieve sustainable control of S. sclerotiorum. Field experiments testing the selected treatments or treatment combinations are needed utilizing different crops and seasons within New Zealand
Copper contamination affects the biogeochemical cycling of nitrogen in freshwater sediment mesocosms
No full textThe effects of trace elements on microbial populations and function can be wide-ranging and difficult to disentangle, hence reports of specific impacts on processes in elemental biogeochemical cycles are rare. This study used a replicated laboratory mesocosm experiment that simulated a flowing watercourse to test the effect of increasing copper concentrations from 6 mg/kg to 30 and 120 mg/kg on nitrogen cycling in a freshwater sediment. After a seven-week equilibration period, the release of nitrous oxide from the treated sediments was measured over three consecutive 24 h periods. This was followed by measurements of copper (Cu), iron, manganese and nitrogen species (nitrate and ammonium) mobilisation in the sediments using diffusive gradients in thin films (DGT), diffusive equilibrium in thin-films (DET) and sequential extractions. Copper is shown to have resulted in significantly reduced nitrate formation near the sediment-water interface and increased nitrous oxide emissions. The concomitant mobilisation and sequestration of iron with ammonium in the sediment with the highest Cu treatment strongly implies links between the biogeochemical cycles of the two elements. This research concludes that modest Cu contamination can affect the nitrogen cycle in freshwater sediments, which may have further implications on water quality and greenhouse gas emissions from freshwater environments
Australasia
Get PDFObserved changes and impacts
Ongoing climate trends have exacerbated many extreme events (very high confidence). The Australian trends include further warming and sea level rise sea level rise (SLR), with more hot days and heatwaves, less snow, more rainfall in the north, less April–October rainfall in the southwest and southeast and more extreme fire weather days in the south and east. The New Zealand trends include further warming and sea level rise (SLR), more hot days and heatwaves, less snow, more rainfall in the south, less rainfall in the north and more extreme fire weather in the east. There have been fewer tropical cyclones and cold days in the region. Extreme events include Australia’s hottest and driest year in 2019 with a record-breaking number of days over 39°C, New Zealand’s hottest year in 2016, three widespread marine heatwaves during 2016–2020, Category 4 Cyclone Debbie in 2017, seven major hailstorms over eastern Australia and two over New Zealand from 2014–2020, three major floods in eastern Australia and three over New Zealand during 2019–2021 and major fires in southern and eastern Australia during 2019–2020
Targeted selective treatment with anthelmintic for New Zealand dairy heifers
No full textAims
To investigate whether measurement of live weight gain (LWG) could be used to deliver targeted selective treatment (TST) with anthelmintic that maintained target live weight (LW) while reducing anthelmintic use.
Materials and methods
Dairy heifers (n = 546) from four commercial, seasonal calving, pastoral New Zealand dairy herds in the Canterbury region of New Zealand were recruited to compare effects of TST, against suppressive treatment (ST), on LW and LWG in their first year at pasture. Animals were enrolled at weaning (December) and weighed ± anthelmintic treatment every month until May and then in August and September before mating in October. All ST calves were treated every month with an oral anthelmintic at 1ml/5kg LW, delivering 0.2mg abamectin, 8mg levamisole and 4.5mg oxfendazole/kg LW, (Control). TST calves received the same anthelmintic at the same time but only if either their individual LWG fell below a pre-specified, time altered, breed specific target for that group (Group target) or if their individual LWG fell below an individual, time altered target for that individual (Individual target). Faecal egg count (FEC) and serum IgA OD levels were recorded from a sample of calves throughout the study.
Results
Compared to ST, anthelmintic use was halved in both TST groups (P 200 EPG grew more slowly in the autumn (P <0.001), but more quickly in the winter (P <0.001). FEC and IgA OD levels were consistent with levels of parasitism sufficient to impact LWG, but there was no evidence for differences between treatment groups. Sensitivity and specificity of LW and LWG as predictors of reaching target weight varied month-on-month but these results suggest monthly LWG and LW were poor indicators for AHC treatment.
Conclusions
TST can be effective in reducing anthelmintic use and maintaining group level performance. As a means of identifying calves for treatment with anthelmintic, LW and LWG sensitivity was 57-85% and 66-93%; specificity 38-83% and 32-79%
Linking farmers to markets: Does cooperative membership facilitate e-commerce adoption and income growth in rural China?
No full textThis study uses the 2020 China Rural Revitalization Survey to investigate the associations between cooperative membership, E-commerce adoption, and household income. Using the conditional mixed process framework, we find that cooperative membership inhibits rural households’ e-commerce adoption, while cooperative membership and e-commerce adoption significantly increase rural household income. The two-stage predictor substitution approach confirms this result. Further, participating in different types of cooperatives has heterogeneous effects on the e-commerce adoption decision and household income growth. However, regardless of whether or which cooperative households participate in, e-commerce adoption significantly increases household income. Policymakers can work with e-commerce enterprises, leverage the current cooperatives, especially the village stock economic and market cooperative, and set up e-commerce cooperatives to popularize e-commerce-related knowledge to encourage e-commerce adoption among rural households. Further, considering the regional disparities in e-commerce adoption, it is essential to strengthen the policy support for the rural households residing in Central and Western China to narrow the “digital divide.
Why using more fertiliser and feed does not necessarily raise dairy farm profits but increases climate harm
Get PDFNew Zealand is in an unusual position in the developed world when it comes to greenhouse gas emissions. About half of all emissions come from agriculture, and almost a quarter can be attributed to biological emissions (nitrous oxide and methane) from the dairy sector