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Physiological stage drives fungal community dynamics and diversity in Leptospermum scoparium (mānuka) flowers
No full textFlowers are an important niche for microbes, and microbes in turn influence plant fitness. As flower morphology and biology change rapidly over time, dynamic niches for microbes are formed and lost. Floral physiology at each life stage can therefore influence arrival, persistence and loss of microbial species; however, this remains little understood despite its potential consequences for host reproductive success. Through internal transcribed spacer 1 (ITS1) community profiling, we characterized the effect of transitioning through five floral stages of mānuka (Leptospermum scoparium), from immature bud to spent flower, and subsequent allocation to seed, on the flower-inhabiting fungal community. We found nectar-consuming yeasts from Aureobasidium and Vishniacozyma genera and functionally diverse filamentous fungi from the Cladosporium genus dominated the anthosphere. The candidate core microbiota persisted across this dynamic niche despite high microbial turnover, as observed in shifts in community composition and diversity as flowers matured and senesced. The results demonstrated that floral stages are strong drivers of anthosphere fungal community assembly and dynamics. This study represents the first detailed exploration of fungi through floral development, building on fundamental knowledge in microbial ecology of healthy flowers
Constraint breeds creativity: A brainstorming method to jumpstart out-of-the-box thinking for sustainability science
No full textConservation science often addresses highly complex issues; creative approaches can help develop new ways of doing so. We describe constraint-based brainstorming, a 10-minute creativity-inducing exercise inspired by design thinking. Although we applied the method with the goal of developing creative environmental valuation methods, it is applicable to almost any complex, interdisciplinary environmental research problem. We tried the approach at two academic workshops, in Japan and in Germany. We generated, in each short activity, scores of unique ideas for the target question. We present this engaging activity as a way to simultaneously achieve multiple outcomes that can support innovative conservation science: quickly generate many seeds of ideas to address a challenge or goal, offer insight into nuances of and shared convictions related to the topic at hand, set a tone of creativity and breaking outside of established thought structures, and build community around a willingness to take risks and freely share ideas
Older, but not wiser: Social wasp colony defensive behavior decreases with time, not experience
No full textBehavioral shifts in animals are often driven by ontogenetic processes such as aging or life experiences, through changes in their physiology and/or gene expression. Colonies of eusocial animals such as social hymenopterans may experience behavioral shifts at the colony-level due to maturation and/or experience throughout the colony cycle. In this study, we investigated the nest defense behavior of social wasp Vespula vulgaris colonies and whether behavioral changes over time or differences in experience with simulated threats can affect aggressive response. Colonies were divided into two treatment groups and experimentally disturbed over a seven-week period by simulating a mammal attack. This procedure was carried out for “hi-freq” colonies on a weekly basis (weeks 1–6), whereas “lo-freq” groups were disturbed once every three weeks (weeks 1, 3, and 7). We show that nest defense behavior in V. vulgaris decreases over time, towards the end of the colony cycle, regardless of how frequently they faced a simulated predator attack. We found no evidence that undisturbed foraging activity or nest size could be used to predict defensive behavior. Our results show anti-predator colony behaviors in Vespula are influenced by the colony cycle, possibly through demographic shifts over time: colonies near their decline are less likely to respond to a simulated threat when compared to earlier in the season. We propose colony behavior is strongly engrained in seasonality and internal development, to a degree that it might overrule the effect of interactions with potential predators
Methodology for development of single cell dendritic spine (SCDS) synaptic tagging and capture model using Virtual Cell (VCell)
Get PDFSingle cell dendritic spine modelling methodology has been adopted to explain structural plasticity and respective change in the neuronal volume previously. However, the single cell dendrite methodology has not been employed previously to explain one of the important aspects of memory allocation i.e., Synaptic tagging and Capture (STC) hypothesis. It is difficult to relate the physical properties of STC pathways to structural changes and synaptic strength. We create a mathematical model based on earlier reported synaptic tagging networks. We built the model using Virtual Cell (VCell) software and used it to interpret experimental data and investigate the behavior and characteristics of known Synaptic tagging candidates.
• We investigate processes associated with synaptic tagging candidates and compare them to the assumptions based on the STC hypothesis.
• We assess the behavior of several reported synaptic tagging candidates against the requirements outlined in the synaptic tagging hypothesis
Associations between physical activity and stress levels in medical doctors working in New Zealand and Australia during initial COVID-19 restrictions
Get PDFIn 2020, the world was gripped by the COVID-19 pandemic which put an unprecedented strain on health care workers. The aim of this study was to assess the effects of the Australian and New Zealand lockdowns on physical activity, depression, and anxiety in medical doctors. We hypothesized that during stressful times such as the COVID-19 pandemic lockdown, physical activity would have a positive effect on the mental health of medical doctors. Convenience sampling (using mass emailing via professional networks including medical associations) and snowball sampling were used during the early period of COVID-19 government mandated restrictions (25 March to 27 April 2020) in New Zealand and Australia. All registered medical doctors working in New Zealand and Australia were eligible to participate in the survey. The short survey collected information demographics, levels of physical activity and mental health using the International Physical Activity Questionnaire: Short Form and the Depression, Anxiety and Stress Scale-42. Of 469 participants who completed the survey, over 81% met the recommended physical activity levels (150 minutes of at least moderate-intensity physical activity/week). Physically inactive New Zealand and Australian medical doctors reported significantly higher depression (p = 0.006), anxiety (p = 0.008) and stress (p = 0.002) scores compared to their active counterparts. This study demonstrated that less physical activity was associated with higher anxiety and depression in medical doctors. A key recommendation from this study is to incorporate greater access to physical activity in healthcare settings for medical doctors
Detection of Alzheimer's disease onset using MRI and PET neuroimaging: Longitudinal data analysis and machine learning
Get PDFThe scientists are dedicated to studying the detection of Alzheimer’s disease onset to find a cure, or at the very least, medication that can slow the progression of the disease. This article explores the effectiveness of longitudinal data analysis, artificial intelligence, and machine learning approaches based on magnetic resonance imaging and positron emission tomography neuroimaging modalities for progression estimation and the detection of Alzheimer’s disease onset. The significance of feature extraction in highly complex neuroimaging data, identification of vulnerable brain regions, and the determination of the threshold values for plaques, tangles, and neurodegeneration of these regions will extensively be evaluated. Developing automated methods to improve the aforementioned research areas would enable specialists to determine the progression of the disease and find the link between the biomarkers and more accurate detection of Alzheimer’s disease onset
Repeated applications of farm dairy effluent treated with poly-ferric sulphate did not adversely affect soil phosphorus availability, P fractions and pasture response — a 4-year field plot study
Get PDFPurpose: Land application of farm dairy effluent (FDE) can cause phosphorus contamination of freshwater due to its high nutrient content especially phosphorus (P) in the animal dung. A novel FDE treatment technology has been developed that uses poly-ferric sulphate (PFS) to treat the FDE and recycle water for washing farmyard and reduce the risk of water pollution from P leaching from through the soil. It is important that the application of PFS-treated FDE (TE) does not cause any adverse impacts on soil fertility or plant growth when the TE is applied to the soil.
Materials and methods: A multi-year field plot study was conducted to determine the effect of repeat applications of FDE and PFS-treated FDE (TE) on soil P availability, P fractionations, plant yield and nutrient uptake. Eight applications of untreated FDE, TE and water as control were applied to replicated soil plots over the period of 4 years. The soil samples were collected on 1 December 2020, and nine pasture samples were harvested during the 2021–2022 dairy milking season. Measurements included soil chemical properties, soil phosphorous fractionations, plant biomass and plant phosphorus and nitrogen uptake.
Results and discussion: The results indicated that the majority of soil fertility indices and soil P fractions had no significant difference between the FDE and TE applications, with the exception of labile P which was significantly higher in the TE (122.7 mg kg‾¹) than in the FDE treatments (103.0 mg kg‾¹) at 0–10-cm soil depth and was also significantly higher in the TE (114.6 mg kg‾¹) than in the FDE treatments (74.0 mg kg‾¹) at 10–20-cm soil depth. Similarly, plant P uptakes and dry matter yields were also the same between the TE and FDE treatments with the average of being 54.4 kg P ha‾¹ and 12.8 t ha‾¹, respectively.
Conclusions: Repeated applications of PFS-treated FDE had no adverse effect on soil P availability or plant growth when compared to untreated FDE application and had the potential to benefit soil fertility compared to control
Californian thistle (Cirsium arvense): endophytes and Puccinia punctiformis
Get PDFCalifornian thistle (Cirisum arvense) is a troublesome weed in pastures and cropping systems. The fungal biocontrol agent Puccinia punctiformis, commonly referred to as thistle rust, performs inconsistently on C. arvense. Problems with P. punctiformis establishment and control of C. arvense may be attributable to differing plant endophytic populations in various environments. This article provides an overview of the relationships between endophytes and their host, but also between endophytes and pathogens with a focus on rust pathogens. This review provides insights into reasons why P. punctiformis performs inconsistently and identifies gaps in our knowledge. Filling these gaps may help to improve performance of this classical fungal biocontrol agent
Biologically dead or wildlife sanctuary? Understanding local attitudes towards New Zealand’s largest brackish lake to promote tourism and conservation
No full textMiscommunication of scientific facts can affect societal attitudes towards lake and wetland use and conservation. In 2005, New Zealand media misrepresented a judge’s statement during a court case, leading to the prevailing discourse that Te Waihora / Lake Ellesmere (TWLE)—New Zealand’s largest brackish lake—was “biologically dead”. The 20-square kilometre lake is in hypertrophic state due to severe nitrogen and phosphorus loading from farms in the catchment. Yet, it still supports high levels of bird, fish, and wetland vegetation biodiversity. It also has very high cultural significance for Ngāi Tahu, the indigenous Māori tribe of the South Island. Residents and visitors use the lake for fishing, gamebird hunting, water sports, cycling, bird watching, camping, and education, among other activities. Furthermore, TWLE is within an hour’s drive from Christchurch International Airport, a major point of arrival for tourists visiting the South Island. Declining environmental quality and negative media discourse affect the lake’s potential to attract domestic and international tourists. In response to these contradictions, we surveyed residents of 740 dwellings located within 20 kilometres from TWLE to analyse their attitudes towards the TWLE environmental quality, wildlife, community, culture, activities, products, and businesses; and to understand their own perceptions about conservation efforts related to TWLE. Statistical analysis shows divergent attitudes and perceptions between groups residing close to and far from the lake. Results can be used to inform strategies that promote culturally and environmentally friendly recreation activities and garner support for policies to reduce pollution, restore TWLE’s water quality, improve wildlife habitat, and promote domestic and international tourism
Comammox bacteria and ammonia oxidizing archaea are major drivers of nitrification in glacier forelands
No full textThis study investigated the abundance of comammox bacteria and canonical ammonia-oxidizing bacteria (AOB) and archaea (AOA), and their relative contribution to nitrification along a chronosequence of deglaciated forelands. The results showed that nitrification related gene abundance tended to increase with glacier retreat, with comammox bacteria and AOA appearing to be the most critical drivers for soil nitrification rates. These findings provide new evidence for the presence of comammox bacteria in glacier forelands and enhance our understanding of the niche differentiation of canonical nitrifier and comammox bacteria