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A mismatch between community assembly and abundance-based diversity indices
Get PDFLong-term ecological studies have consistently reported slower than expected changes in biodiversity over time. One explanation for this phenomenon is that commonly used diversity measurements such as species richness are too coarse to detect mechanisms shaping community assembly. Theory suggests that similar phenomena may occur in abundance-based diversity measurements, but the extent of this problem is currently unclear. We confront this theoretical prediction with field data by studying temporal changes in abundance-based diversity indices across 3341 observations from 880 plots in 15 long-term vegetation plot studies. We then partition diversity change into mechanisms of interest to ecologists: selection, drift, and immigration. We show that these resulting changes in relative abundances often produce non-linear changes in diversity. These non-linearities lead counterintuitive effects that are easy to miss when directly analysing changes in diversity. To resolve this we show that explicit partitioning of diversity change leads to one further, less-studied partition: ‘rarity shifts'. Rarity shifts measure how an individual's contributions to diversity changes over time. These rarity shifts are responsible for counter-intuitive effects, for example when radical changes in community composition lead to negligible changes in diversity. We found rarity shifts are an important component of diversity change across many studies. Furthermore, rarity shifts tend to oppose selection, drift and immigration. Therefore, rarity shifts explain why changes in relative abundance do not consistently result in changes in abundance-based diversity measurements. Ultimately, using rarity shifts can lead to a more accurate understanding of the temporal rate and nature of diversity change in ecology and conservation
Alterations in the axon initial segment plasticity is involved in early pathogenesis in Alzheimer's disease
No full textAlzheimer's disease (AD) is the most prevalent neurodegenerative disorder, characterized by the early presence of amyloid-β (Aβ) and hyperphosphorylated tau. Identifying the neuropathological changes preceding cognitive decline is crucial for early intervention. Axon initial segment (AIS) maintains the orderly structure of the axon and is responsible for initiating action potentials (APs). To investigate the role of AIS in early stages of AD pathogenesis, we focused on alterations in the AIS of neurons from APP/PS1 mouse models harboring familial AD mutations. AIS length and electrophysiological properties were assessed in neurons using immunostaining and patch-clamp techniques. The expression and function of ankyrin G (AnkG) isoforms were evaluated by western blot and rescue experiments. We observed a significant shortening of AIS in APP/PS1 mice, which correlated with impaired action potential propagation. Furthermore, a decrease in the 480 kDa isoform of AnkG was observed. Rescue of this isoform restored AIS plasticity and improved long-term potentiation in APP/PS1 neurons. Our study implicates AIS plasticity alterations and AnkG dysregulation as early events in AD. The restoration of AIS integrity by the 480 kDa AnkG isoform presents a potential therapeutic strategy for AD, underscoring the importance of targeting AIS stability in neurodegenerative diseases
The interrelationship between affect and cognition in destination choice decision-making : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
Get PDFDestination choice decision-making of travellers has been extensively researched in the travel and tourism literature. Its complexity and dynamic nature have been explored often through normative and prescriptive perspectives and, more recently, process studies. Underemphasised in this literature have been travellers’ emotions despite their prominence in the decision-making experience and their constitutive roles in evaluations carried out in decision-making along with cognition. This thesis aimed to investigate the interrelationships between affect and cognition in the destination decision-making of leisure travellers. This exploratory inquiry adopted qualitative research methods to collect detailed descriptions of travel decision making, including personal and socio-cultural background and characteristics of the decision makers. Data collection involved semi-structured interviews with 28 post-graduate students at Lincoln University which were thematically analysed. On the basis of the findings and analysis, it is concluded that affect does not play a subservient role, relative to cognition, in the process of destination decision-making. In fact, contrary to some everyday intuitions about affect, it was also found that, far from undermining the destination decision-making process, affect has multifunctional capabilities such as providing informational input, navigating decisions in relation to commitment, direct attention to significant considerations (concerns), and enabling travellers to make faster judgments.
Also, affect allows the decision maker to engage with their previous experiences, personal beliefs and attitudes and the interpersonal, social and cultural contexts within which the decision process occurs. Affects perform specific roles in integrating diverse affective qualities into the decision-making process in tandem with personal and socio-cultural factors. Such elicited affects interactively function along with cognition in an entangled manner throughout the choice process. The picture of destination decision-making that emerges is one in which cognition and affect interweave in such a way that draws into the decision-making the relevant personal characteristics and broader contexts involved. The thesis concludes by highlighting the theoretical and practical insights into travel decision-making that stem from this interactive understanding of the roles of cognition and affect in destination decision-making
Point of view
No full textDr Amber Parker was guest speaker at the 2024 Southern Pinot Noir Workshop in Hanmer, sharing insights on potential impacts of climate change on viticulture, along with adaptation opportunities, particularly with regard to Pinot Noir. Amber, who is Lincoln University’s Director of the Centre for Viticulture and Oenology, shares some of her learnings
Bibliometric analysis of InsurTech
Get PDFInsurTech, derived from "insurance technology," refers to technology and innovation whose primary goals are to provide better services and technology to the insurance industry in the current progressive technological environment and industrial revolution. That industry increasingly relies on technology to obtain a competitive advantage and it assists decision-makers make better decisions. We use bibliometric analysis to assess the trend in InsurTech. We analyse all InsurTech-related publications on Scopus: 175 articles based on keywords relevant to InsurTech in the articles’ titles, keywords, and abstract. Frequency analysis and data visualisation use Microsoft Excel, VOSviewer and the Bibliometric R package. We use standard bibliometric indicators: publication year, document type, source type, source title, language, subject area, keyword analysis, geographical distribution, authorship, and citation analysis. There has been a remarkable increase in the number of publications on InsurTech since 2017. The growing number of InsurTech publications demonstrates the importance of technology in the insurance sector and will undoubtedly affect the economy and society. Keyword analysis indicates that using insurance big data in various studies requires a theoretical link with the InsurTech topic and the insurance contract, which is a potential topic for future study
Evaluating the in vitro efficacy of varied concentrations of abamectin and fluopyram, alongside different durations and temperatures of hot water treatments against Meloidogyne incognita, the southern root-knot nematode
No full textPlant germplasm importation into Aotearoa/New Zealand poses a risk of introducing unwanted organisms. Current biosecurity measures for plant nematodes on imported nursery stock are under review. This study aimed to investigate alternative chemicals that could replace fenamiphos, the current border treatment. Abamectin and fluopyram were chosen for assays based on their demonstrated nemoticidal activity and availablity. Hot water submersion was also tested as a non-chemical alternative. Second stage juveniles (J2s) of Meloidogyne incognita were isolated from infected susceptible tomato cultivars (Solanum lycoperisicum). Preliminary experiments tested the field rates of abamectin (0.009 g/L a.i) and fluopyram (0.3 g/L a.i.) on J2s, with resulting mortality rates of 54.6% and 78.6%, respectively. Preliminary hot water experiments for 3 hours at 44°C showed complete mortality of J2s. Further experiments with abamectin (0.009, 0.018, 0.045 and 0.09 g/L a.i.) and fluopyram (0.3, 0.6, 1.5 and 3.0 g/L a.i.) showed that the highest mortality rate with abamectin was 75.2%. Concentrations of fluopyram ≥ 0.6 g/L resulted in 100% mortality. Hot water treatments for 1 and 2 hours at 44 and 50°C also resulted in 100% mortality. Further experimentation using in planta bioassays are recommended to assess how fluopyram affects nematodes contained within plant tissues. Overall, the study demonstrated the potential of fluopyram and hot water submersion which provided the complete mortality required in biosecurity situations as an alternatives to fenamiphos for biosecurity measures in Aotearoa/New Zealand
The potential of UAV and very high-resolution satellite imagery for yellow and stem rust detection and phenotyping in Ethiopia
Get PDFVery high (spatial and temporal) resolution satellite (VHRS) and high-resolution unmanned aerial vehicle (UAV) imagery provides the opportunity to develop new crop disease detection methods at early growth stages with utility for early warning systems. The capability of multispectral UAV, SkySat and Pleiades imagery as a high throughput phenotyping (HTP) and rapid disease detection tool for wheat rusts is assessed. In a randomized trial with and without fungicide control, six bread wheat varieties with differing rust resistance were monitored using UAV and VHRS. In total, 18 spectral features served as predictors for stem and yellow rust disease progression and associated yield loss. Several spectral features demonstrated strong predictive power for the detection of combined wheat rust diseases and the estimation of varieties’ response to disease stress and grain yield. Visible spectral (VIS) bands (Green, Red) were more useful at booting, shifting to VIS–NIR (near-infrared) vegetation indices (e.g., NDVI, RVI) at heading. The top-performing spectral features for disease progression and grain yield were the Red band and UAV-derived RVI and NDVI. Our findings provide valuable insight into the upscaling capability of multispectral sensors for disease detection, demonstrating the possibility of upscaling disease detection from plot to regional scales at early growth stages
Association between yoga participation and arterial stiffness: A cross-sectional study
Get PDFBackground: Yoga may help adults of all fitness levels increase their physical activity and decrease their cardiovascular disease risk.
Aim: To determine if arterial stiffness is lower (beneficial) in yoga versus non-yoga participants. Method: This cross-sectional study included 202 yoga (48.4 + 14.1 years, 81% female) and 181 (42.8 + 14.1 years, 44% female) non-yoga participants. The primary outcome was carotid–femoral pulse wave velocity (cfPWV). The two groups were compared using analysis of covariance with adjustments for demographic (age and sex), hemodynamic (mean arterial pressure and heart rate), lifestyle (physical activity levels, sedentary behaviour, smoking status and perceived stress score) and cardiometabolic (waist-to-hip ratio, total cholesterol and fasting glucose) factors.
Results: Following adjustments, cfPWV was significantly lower in yoga compared to non-yoga participants with a mean difference: –0.28 m.s‾¹, (95% CI = –0.55 to 0.08).
Conclusion: At a population level, yoga participation may assist with decreasing the risk of cardiovascular disease in adults
Editorial: Eliciting plant defense responses: From basic to applied science for sustainable agriculture
Get PDFPlants constantly face a diversity of pathogens and insects that affect food production. Synthetic agrochemicals are often use to overcome these challenges. However, current demands for stringent worldwide regulatory policies led to the development of sustainable agriculture strategies, including naturally-derived molecules that elicit plant defense responses (Scariotto et al., 2021). The commercial use of these molecules is still limited, mostly due to poor knowledge on the molecular mechanisms producing their effects on plant metabolism. In recent decades, efforts have been directed toward understanding how individual molecules, such as immune receptors or microbial effectors, enable plants to perceive and respond to pathogens, insects, and other stresses. Furthermore, recent research on plant immunity has revealed high levels of complexity, including regulation mediated by micro-peptides and miRNA. Such knowledge opens the opportunity to link basic and applied science to facilitate using natural elicitors as a sustainable option for crop protection