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Productive and nutritional parameters in diverse pastures composed of complementary species (Lolium perenne L., Bromus valdivianus Phil., Dactylis glomerata L., and Trifolium repens L.) under the leaf regrowth stage defoliation criterion
No full textThe diversification of plant species within intensively managed pastures has been proposed as an alternative to conventional pure sward systems in an effort to address climatic-driven issues of pasture-based livestock production. In a diverse pasture composed of complementary species (DPCS), individual species fulfil different agroecological niches and complement each other. It is expected that DPCS have a greater capability to tolerate and perform under increasingly extreme climate events; however, appropriate grazing management strategies for diverse pastures still need to be fully elucidated. In the present study, DPCS comprised Lolium perenne L., Bromus valdivianus Phil., Dactylis glomerata L., and Trifolium repens L. The leaf regrowth stage [LS; L. perenne (2.5–3.0LS), B. valdivianus (3.5–4.0LS) and D. glomerata (3.5–4.0LS)] is proposed to be an applicable method of defoliation management for DPCS due to a potential overlapping of their optimal defoliation intervals. The productive, morpho-physiological, and nutritional parameters of DPCS and their respective single-grass and T. repens pastures were assessed for two years under the LS criterion for defoliation. Within the DPCS, the three grass species presented a temporal overlapping of their respective LS intervals. Significant differences were found in the dry matter seasonal accumulation; DPCS exhibited seasonal asynchronous growth among species and presented an enhanced ability to withstand the ingress of volunteer species. In all pastures, the nutritional parameters were mostly influenced by season and LS criterion. Lolium perenne, B. valdivianus, and D. glomerata were shown to be complementary grass species, presenting growth asynchrony and an overlapping defoliation interval that optimised production. In this study, grazing management that focuses on the morpho-physiological development of grasses within a diverse pasture was successfully applied, with B. valdivianus LS optimal interval for defoliation being the most appropriate criterion for determining a grazing regime for DPCS.fals
Shifting roles of renewable and fossil energy in the ENTSO-E countries: Evidence from a novel war-induced energy intensity index
No full textThe Russia-Ukraine war, escalating in February 2022, severely disrupted European energy markets. This conflict significantly increases energy security concerns and drives costs to unprecedented levels. This study investigates the evolving roles of renewable and fossil energy in mitigating this insecurity. We introduce a novel War-Induced Energy Intensity (WEI) index, constructed from over 507,574 news reports and tweets using large language models (LLMs). Our employed LLMs enable us to apply a scoring framework that precisely captures the intensity of fossil energy induced by the war. Validation tests across 24 European countries confirm that our WEI outperforms existing geopolitical risk indices in explaining wholesale electricity market dynamics. A structural break test identifies a significant market shift in early 2022, coinciding with the conflict's outbreak. This provides a statistical basis for our pre- and post-conflict analysis, which reveals a reversal of roles. Before 2022, fossil fuels played a stabilizing role in electricity markets. After the conflict began, their supply disruptions exacerbated market risks. In contrast, renewable energy sources – particularly wind, solar, and hydropower – emerged as key stabilizers, significantly reducing market instability. These findings underscore the growing importance of renewables in ensuring energy security during geopolitical crises.fals
Hunting down what makes good bacteria bad company : a study investigating the genetic and phenotypic differences between Limosilactobacillus fermentum AGR1485 and AGR1487 to elucidate the molecular basis underlying L. fermentum AGR1487's barrier-disruptive phenotype : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy, Massey University, Manawatū, New Zealand
No full textBackground: Bacteria play crucial roles in human society, from food production to natural symbiosis. Among these, probiotic species such as Limosilactobacillus fermentum are widely recognised for their health benefits, although not all strains exhibit equivalent properties. Notably, strain AGR1487 of L. fermentum has been identified as an outlier, exhibiting a barrier-disruptive phenotype in an in vitro model of the intestinal epithelial barrier. Disruption of this barrier is clinically relevant, as it can increase intestinal permeability, facilitate translocation of luminal antigens or pathogens, and contribute to gastrointestinal disorders, including inflammatory bowel disease and irritable bowel syndrome. The in vitro model employs Caco-2 cells, derived from human colorectal adenocarcinoma, which differentiate into enterocyte-like cells, and measures transepithelial electrical resistance (TEER) to assess barrier function. In contrast, strain AGR1485, isolated from the same human population, does not display a barrier-disruptive phenotype. This study investigates the genetic and phenotypic differences between AGR1485 and AGR1487 to elucidate the molecular basis underlying the barrier-disruptive phenotype.
Methods: A variety of methods, including a multi-omics approach, were employed to analyse the genetic and phenotypic differences between AGR1485 and AGR1487. The barrier-disruptive phenotype was confirmed through TEER assays. Growth characteristics were assessed using spectrophotometry, and bacterial morphology was examined via electron microscopy. Genomic sequencing was performed using hybrid assembly approaches, combining Illumina short-read and PacBio long-read sequencing. Comparative genomic and transcriptomic analyses of both strains were conducted to identify non-identical genes and differential gene expression patterns.
Results: TEER assays demonstrated that AGR1487 significantly disrupts intestinal barrier integrity (-20.11 % TEER per hour), whereas AGR1485 had minimal effects. Electron microscopy revealed AGR1487’s tendency to autoaggregate, a feature absent in AGR1485. Both genomes were sequenced, and the assemblies were of exceptionally high quality, with BUSCO completeness scores of 99.5 % (98.8 % single-copy, 0.7 % duplicated, 0.5 % fragmented, 0 % missing), confirming their suitability for detailed comparative and functional analyses. Comparative genomic analysis showed that AGR1487 possesses 62 non-identical genes within regions of high genomic variability, suggesting horizontal gene transfer events and diversification or loss of these genes in other strains. Transcriptomic profiling indicated that AGR1487 expresses these non-identical genes before TEER assays, with 25 candidate genes potentially implicated in its barrier-disruptive properties. Among them, a phage-associated truncated metallopeptidase and mucin-binding protein were identified as strong candidates.
Conclusion: The findings of this PhD thesis highlight strain-specific variations within L. fermentum, emphasising the necessity of evaluating probiotics at the strain level. The identification of genetic elements responsible for the barrier-disruptive phenotype in AGR1487 underscores the complexity of bacterial-host interactions and the need for careful screening in probiotic applications. Future research will focus on the functional validation of candidate genes through knockout and complementation studies to confirm their roles in gut barrier integrity disruptio
Weathering the storm: How does firm oil price uncertainty exposure impact green innovation in times of geopolitical tensions
No full textThis study examines the impact of oil price uncertainty sensitivity on corporate green innovation, in times of geopolitical tensions. Using manually collected import and export data at the destination country-firm level from China Customs Dataset, we construct the unique measure of firm-level geopolitical tensions of Chinese listed companies received from foreign supply chain partners. Our results reveal that firms with higher exposure to oil price uncertainty are more likely to engage in green innovation. Importantly, geopolitical tensions significantly and positively moderate the relationship between corporate oil price uncertainty exposure and green innovation efforts, with the effect being particularly pronounced in the context of geopolitical tensions originating from customer countries. Further analysis reveals that domestic supply chain alliances and supply chain efficiency mitigate firms' urgency for green innovation. Finally, we find that the effects of oil price uncertainty and geopolitical tensions on green innovation are more pronounced in firms with higher international exposure, and greater competitive pressures.fals
Biofilm formation of Pseudomonas spp. at the air-liquid interface, EPS matrix composition and resistance to CIP cleaning : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New Zealand
No full textPseudomonads are known for their spoilage potential due to the production of thermostable enzymes and pigments. Pseudomonads can affect a wide range of processing environments, including dairy, poultry, meat, fish, and vegetable processing. The proteolytic, lipolytic and pectolytic enzyme production associated with pseudomonads was witnessed in the past. The high persistence of pseudomonads is observed due to their biofilm formation on food contact surfaces, especially under cold temperatures (e.g. 4°C) and at the air-liquid interface and submerged conditions. Despite the incidences reported of pseudomonad spoilage, limited information exists on their biofilm formation at cold temperatures, matrix compositional differences on food contact surfaces, and how the biofilm formation at cold temperatures affects the cleaning processes. This thesis addresses these research gaps by studying the biofilm formation and matrix composition of pseudomonads at cold temperatures and their control strategies.
Among the eleven isolates studied, two isolates, P. lundensis and P. cedrina were identified as strong biofilm formers at cold temperatures with higher biomass and cell counts. This study identified that these two isolates are cellulose-only producers and can form strong biofilms in the absence of curli fibres. The characterization of the extracellular polymeric substances EPS composition revealed that the cold temperatures encouraged increased matrix production with polysaccharides, proteins, and extracellular DNA, which resulted in complex biofilm architecture. The cell-to-EPS ratio was much higher in the biofilms formed on stainless-steel surfaces compared with those on polystyrene surfaces, explaining the influence of temperature and surface type on the biofilm formation of these isolates.
The air-liquid interface promoted higher EPS production, as confirmed by the overexpression of EPS-encoding genes in air-liquid interface biofilm cells compared to their submerged counterparts. These findings demonstrate the air-liquid interface as a favourable niche in the biofilm formation of pseudomonads. The cleaning simulation with traditional CIP revealed the EPS footprints left on the stainless-steel surface. The potential of these footprints during recolonisation was shown in both strong and weak biofilm formers. The removal of these footprints using commercial enzyme cleaners resulted in less aggressive biofilm formation during recolonisation.
Overall, this thesis addresses the critical research gaps in the biofilm formation of psychrotrophic pseudomonads under cold temperatures. Linking the EPS composition, biofilm architecture and at the different surfaces and interfaces provides practical insights improving cleaning and sanitation and finally reduces the spoilage incidents of these pseudomonad isolates
Eucommia ulmoides leaf as an alternative substrate for kombucha fermentation: the role of microbial communities in dynamics and metabolic profile
No full textEucommia ulmoides leaf (EUL) was introduced as a novel fermentation substrate to replace traditional tea in kombucha. High-performance liquid chromatography, untargeted metabolomics, and high-throughput sequencing were applied to understand the potential relationships during fermentation. EUL kombucha exhibited slower sugar consumption rate and superior in vitro antioxidant activity compared with traditional kombucha. Total polyphenols, geniposidic acid, pinoresinol diglucoside, and rutin demonstrated an increasing trend, whereas total flavonoids and chlorogenic acid contents considerably decreased. Metabolite profiling revealed 211 positive and 165 negative ion components in samples fermented for 0, 4, and 8 days. Komagataeibacter and Gluconobacter were the dominant bacterial genera while Hanseniaspora , Dekkera , and Kregervanrija dominated the yeast community. The dominant microbial genera could have regulated nucleotide metabolism, pentose and glucuronic acid–related conversions, ascorbic acid and aldehyde metabolism, and flavonoid biosynthesis, leading to changes in the expression of differential metabolites of EUL kombucha. The findings support innovation in kombucha development.fals
Exploring the role of model classification, complexity, and selection in volcanic hazard forecasting
No full textThis review examines the current landscape of computational volcanic hazard models, focusing on their creation and application, for a diverse set of end-users’ short-term and long-term forecasting requirements. We provide a comprehensive classification of volcanic hazard models, categorising them according to their theoretical foundations. This is central to understanding the diversity of hazard characterisation and simulation approaches, from empirical models to computationally demanding physics-based numerical models. The classification framework helps contextualise the strengths and limitations of different models and their suitability for specific forecasting demands. We discuss the fundamental principles behind model construction, considering factors such as input parameters, conceptual frameworks, and the incorporation of uncertainties. We also synthesise existing literature on model testing, covering aspects such as model verification, validation, calibration, and benchmarking, and provide a systematic and transparent framework for model selection, considering data availability, computational constraints, and specific forecasting needs. We explore the balance between model complexity, computational efficiency, and accuracy, addressing the uncertainties inherent in both input parameters and model processes. A key focus is the role of input parameters in forecasting and the need to select models that are detailed enough to capture essential hazard dynamics, yet simple enough to minimise error and computational costs.fals
Thermal taster status: A review of physiological aspects, methodological variables in phenotypical characterisation and relationship with sensory perception and affective response
No full textThermal taster status (TTS), the ability to perceive tastes from lingual thermal stimulation, is a phenotype first observed in 2000. Due to limited data available, knowledge on this phenotype is still scarce. This review assessed existing literature (from 2000 to 2025) on TTS considering physiological aspects; methodological variables related to the determination of TTS and participant classification; socio-demographic factors and other orosensory phenotypes; the relationship between TTS and consumer affective responses to food and beverage. It showed that TTS represents a source of individual taste variation that discriminates between thermal tasters and thermal non-tasters, where the former are found to be more responsive to taste and chemesthetic sensations, in watery solutions, beverages and liquids. Despite only a few studies evaluating the effect of TTS on food and beverage sensory perception, it emerged that TTS could have an influence on food liking. However, several limitations in this field of research were identified and future research perspectives are suggested. This review contributes to understanding how this taste phenotype may play a key role in food preferences, food intake, and diet-related diseases. A deeper understanding of the impact of TTS on sensory perception through future research is warranted.fals
Exploring student perspectives of Expert by Experience involvement in Clinical Psychology training using a story completion method : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Clinical Psychology at Massey University, Manawatū, Aotearoa New Zealand. EMBARGOED until 2 September 2026
No full textEmbargoed until 2 September 2026The Lancet Commission have identified the urgent need to eradicate mental health stigma and discrimination. A key recommendation to support this is mandating teaching on the needs and rights of people with mental health conditions, co-delivered by people with lived experience, in health and social professional and vocational training courses. However, the involvement of people with lived/living experience of mental distress, or ‘experts by experience’ (EBE), in clinical psychology training in Aotearoa is minimal. Barriers to increasing effective EBE involvement may be found in student attitudes. The aim of my research was to explore student perspectives of EBE involvement in clinical psychology training. Using a story completion method, I explored the assumptions, ideas, and language that participants engaged with when writing about EBE involvement, to help elucidate social understandings that underlie student perspectives. The stories produced by participants contained several tensions. Firstly, participants contrasted the humanity provided by EBE involvement with the dominance of a biomedical approach in training that views mental distress in less than human ways. Secondly, EBE expertise was valued, but was also devalued if it challenged the superiority of psychology, or the expert role of students and psychologists. Thirdly, students were depicted as relating to and connecting to EBE experience, but also as unable to understand and as othering of EBE. These findings highlight the need for a shift in how mental distress is viewed, and the way knowledge is produced and valued within psychology. Such a shift requires changes at the teaching, organisational, and wider disciplinary level, including through supporting EBE in leadership roles, and making changes to organisational policy, accreditation standards, training requirements, and professional competencies. Such change would support the meaningful involvement of EBE in clinical psychology training, and the eradication of mental health stigma and discrimination in higher education
Can administrative data be used for a national register of hospitalised stroke patients? A New Zealand validation study
No full textBackground
Using community-based incidence studies and clinical registries to assess stroke care and outcomes is resource intensive and often geographically limited. Linked administrative data are lower-cost and wider-reaching, but potentially less accurate and complete. This study compared administrative data to national hospital-based study data to assess whether administrative data represents a valid alternative.
Methods
We linked and compared data from the REGIONS Care Study, a New Zealand nationwide observational study, with administrative data from Statistics New Zealand’s Integrated Data Infrastructure (IDI). Sensitivity, specificity, positive predictive value, and Cohen’s kappa coefficient were used to assess case identification, risk factors, post-stroke outcomes, and interventions as applicable. Additional audits explored the validity of IDI ‘true false positives.’
Findings
From May to July 2018, 1719 patients with stroke were captured in REGIONS Care and 1833 in the IDI. Using REGIONS Care as the reference standard, the sensitivity of the IDI for stroke case identification was 83% and the positive predictive value 77%. There were 300 false-negatives and 414 false positives. The audit of two hospitals showed that some cases identified in IDI but excluded by REGIONS were actual strokes. For stroke risk factors, the IDI showed high sensitivity and specificity for diabetes (93% and 91%, respectively), atrial fibrillation (87% and 90%), and smoking (71% and 97%) but lower specificity for hypertension (61%), and dyslipidaemia (52%). A derived IDI favourable outcome measure showed good agreement with the modified Rankin Scale (sensitivity 88%, specificity 82%, kappa 0.67). The IDI accurately identified post-stroke medication use (sensitivities 81%–94%, specificities 78%–91%) and thrombectomy interventions (sensitivity 88%, kappa 0.91).
Interpretation
The use of administrative data to ascertain stroke cases, risk factors, interventions and outcomes was feasible and compared well with manual hospital data collection making an administrative data based national stroke register possible, although supplementary data collection for comprehensive care evaluation may be required.
Funding
The study was funded by the NZ Health Research Council (HRC 17/037).fals