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Ovarian follicle size or growth rate can both be determinants of ovulatory follicle selection in mice
No full textThe endocrinology regulating ovulation of the desired number of oocytes in the ovarian cycle is well described, particularly in mono-ovulatory species. Less is known about the characteristics that make one follicle suitable for ovulation while most other follicles die by atresia. Bromodeoxyuridine (BrdU) injection was used to characterize granulosa cell proliferation rates in developing ovarian follicles in the estrous cycle of mice. This methodology allowed identification of follicle diameters of secondary (80-130 μm), follicle-stimulating hormone (FSH)-sensitive (130-170 μm), FSH-dependent (170-350 μm), and preovulatory (>350 μm) follicles. Few preovulatory-sized follicles were present in the ovaries of mice at estrus, the beginning of the cycle. Progressive increases were seen at metestrus and diestrus, when full accumulation of the preovulatory cohort (∼10 follicles) occurred. BrdU pulse-chase studies determined granulosa cell proliferation rates in the 24-48 h before the follicle reached the preovulatory stage. This showed that slow-growing follicles were not able to survive to the preovulatory stage. Mathematical modeling of follicle growth rates determined that the largest follicles at the beginning of the cycle had the greatest chance of becoming preovulatory. However, smaller follicles could enter the preovulatory follicle pool if low numbers of large antral follicles were present at the beginning of the cycle. In this instance, rapidly growing follicles had a clear selection advantage. The developing follicle pool displays heterogeneity in granulosa cell proliferation rates, even among follicles at the same stage of development. This parameter appears to influence whether a follicle can ovulate or become atretic
Effects of travel
No full textPlaying sport at home is advantageous for the home team for many reasons including fan support, familiarity but probably most of all they don’t have to travel. The away team must overcome changes to their normal routines and protocols, put up with what can sometimes be a hostile home crowd as well as getting through the negative effects of travel. Previous work in this area shows that home teams typically win more than 50% of their games due to their familiarity with conditions, local encouraging crowds, and lack of travel, with teams less likely to win away games particularly if their required travel is long-haul (George et al. 2015; Lo et al. 2021; Read et al. 2021). This information requires practitioners like strength and conditioning trainers and coaches to consider the negative effects of travel when performance planning
Contrasting response of comammox Nitrospira, ammonia oxidising bacteria, and archaea to soil pH and nitrogen inputs
No full textThis study aimed to investigate the effect of soil pH change, and nitrogen amendment on ammonia oxidiser abundance and comammox Nitrospira community composition. The experimental design used soil mesocosms placed in a temperature-controlled incubator for 90 days. A Templeton silt loam was used as its physiochemical properties are typical of the region's dairy farms. The results showed that comammox Nitrospira clade B preferred the natural (pH 6.1–6.2) soil pH with no applied nitrogen. Furthermore, synthetic urine (N700) decreased the abundance of comammox Nitrospira clade B. This may have been because the large amounts of available ammonia in the N700 treatments inhibited the growth of comammox Nitrospira. These results suggest that while comammox Nitrospira clade B are present in New Zealand dairy farm soils, but their role in nitrification in the very high nitrogen environment under a urine patch in grazed pastures may be limited. Further research is needed to confirm this. In contrast to comammox, the AOB community (dominated by Nitrosospira) responded positively to the application of synthetic urine. The response was greatest in the high pH soil (7.1), followed by the natural and then the low pH (4.9) soils. This may be due to the difference in ammonia availability. At high pH, the ammonia/ammonium equilibrium favours ammonia production. Calculated ammonia availability in the N700 treatments accurately predicted the AOB amoA gene abundance. Interestingly, the AOA community abundance (which was predominantly made up of Thaumarchaeota group I.1b clade E) seemed to prefer the natural and high pH soils over the low pH. This may be due to the specific lineage of AOA present. AOA did not respond to the application of nitrogen
Investigation of the microbiome structure and function in grapevines escaping trunk diseases
No full textGrapevine trunk diseases (GTD) represent a major challenge to the viticulture industry in New Zealand and other winegrowing regions worldwide. Due to the limited availability of effective control strategies for these intractable diseases there is increased interest in identifying alternative control strategies, including biological control. In some New Zealand vineyards, vines that remain healthy in a background of heavy GTD pressure have been observed. In this study, vineyards in two grape growing regions, Hawke's Bay and Canterbury, were surveyed for the presence of grapevines escaping GTD, referred to as disease escape vines. Woody trunk tissue samples were collected from these putative disease escape vines and the surrounding diseased vines. DNA metabarcoding of the ribosomal internal transcribed spacer 1 (ITS1) and 16S ribosomal RNA gene was used to characterise their fungal and bacterial communities. The results showed that the status of the vine as either GTD escape or diseased was a significant determinant of the bacterial and fungal microbiome structure of the grapevine trunk. The bacterial taxa Pseudomonas and Hymenobacter were consistently at higher relative abundance in GTD escape vines, whilst the fungal taxa Aureobasidium, Seimatosporium, Cladosporium, and Rhodotorula were differentially associated with GTD escape vines. In contrast, the GTD pathogen Eutypa lata was associated with diseased vines. Bacterial and fungal isolates matching the key taxa identified by DNA metabarcoding from GTD escape vines were retrieved from the cultures recovered from the vines and tested for inclusion in a synthetic microbial community (SynCom). Additional selection criteria for inclusion were the microorganism's functional properties, such as not being a known plant pathogen, not causing lesions on grapevine shoots, and demonstrating inhibitory activities against the GTD pathogens E. lata and Neofusicoccum luteum in dual culture plate assays. Using these criteria, Aureobasidium pullulans, Seimatosporium vitis, and
seven Pseudomonas isolates were selected as consortium members. Combined and separate fungal
and bacterial consortia were tested in plant assays against the GTD pathogens E. lata and N. luteum.
After 3 months, the bacteria successfully established and persisted within the grapevines, significantly altering the grapevines' microbiome structure. Treatment with combined bacterial and fungal consortia resulted in significantly shorter lesions than the pathogen controls. These results highlight the potential for using selected microbial consortia as a promising strategy for controlling GTD pathogens in planta
Introduction: indigenous self-governance in the Arctic States
No full textThe theme of this special issue is indigenous self-governance in Arctic states. A common characteristic of the states that are partly located in the Arctic – Canada, Denmark, Finland, Norway, Russia, Sweden, USA – is that they all have indigenous peoples, and all have some form of self-government. There has been relatively little research on the similarities and differences between the sub-state autonomy structures within the Arctic states from a political science perspective (although with important exceptions, see below). This is somewhat surprising given the growing interest in the Arctic region during the last 15 years, where some of these autonomous units play an increasingly important role. This special issue asks how different are these self-governing units? How did they evolve into their current form? Do they have a distinct Arctic indigenous character
Evaluating indigenous forest restoration design strategies in support of biodiversity and pastoral farmers in marginal hill country, Aotearoa New Zealand : A dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Landscape Architecture. at Lincoln University
No full textStrategically reforesting marginal hill country with indigenous forest is a recognised way to aid in decelerating and reversing the dual climate and biodiversity crisis in Aotearoa New Zealand, with the potential to provide income to farmers simultaneously. Farm owners are needed to assist in reforestation if it is to occur on a significant scale; however, there is a need for further contributions about what spatial reforestation strategies are effective in concurrently meeting biodiversity and farm owner requirements on marginal hill country land.
A narrative literature review was conducted to identify bush bird, lizard and insect wildlife guild and farm owner requirements to establish evaluation criteria. Wildlife guilds require appropriate spatial configurations of habitat size, connectivity and resources. Farm owners require restoration strategies that are low cost, easy to implement, easy to maintain, and timely (particularly to generate income through carbon sequestration under the New Zealand Emissions Trading Scheme (NZ ETS)). Attributes that lead to these restoration outcomes were also identified as important in evaluating and defining strategy effectiveness measures.
These criteria were then applied through a literature review to critically evaluate the effectiveness of existing hill country restoration establishment methods and spatial configuration strategies New Zealand wide. The results indicate that none of the existing strategies meet all criteria for a high level of effectiveness. A third narrative literature review identified design solutions to create an improved strategy through the realm of landscape ecology and landscape networks. The novel hill country restoration strategy was designed by combining principles of the patch-corridor-matrix theory, spatial eligibility criteria for the ETS and strengths of existing strategies. When analysed using the evaluation criteria, the novel strategy met all criteria effectively. However, only biodiversity interaction and ability to receive NZUs criteria were met to high effectiveness, with the cost of establishment, ease of establishment and cost/ease of maintenance only being averagely effective.
These results indicate there is a substantial need for improvement of policy and development of on-the-ground restoration strategies, to assist both farm owners and resulting biodiversity in restoring marginal hill country land, in answer to the increasingly urgent dual biodiversity and climate crises we are facing
Land use conversion to uplands significantly increased the risk of antibiotic resistance genes in estuary area
No full textLand use conversion in estuary wetlands may affect the transmission of antibiotic resistance genes (ARGs), while the risk rank of the ARGs and the change of clinically relevant ARGs under various land-use types are not well understood. This study used metagenomics to reveal the diversity and abundance of ARGs across five distinct land uses: reed wetland, tidal flat, grassland, agricultural land and fallow land, as well as their distribution and potential health risks. Results showed that high numbers of ARG subtypes and classes were detected irrespective of land-use types, notably higher in agricultural land (144 ARG subtypes). The most shared ARG subtypes were multidrug resistance genes across all the land uses (29 subtypes, 4.7 × 10¯²-1.5 × 10¯¹ copies per 16S rRNA gene copy). Proteobacteria and Actinobacteria were primary ARG hosts, with 18 and 15 ARGs were found in both of them, respectively. The ARG subtype mdtB was the most dominant clinical ARG detected with 90 % amino acid identity. The change of ARGs exhibited a consistent trend across land uses in terms of health risk ranks, with the highest observed in fallow land and the lowest in reed wetland. This study reveals the distribution pattern of ARGs across various land-use types, and enhances our understanding of the potential health risks associated with ARGs in the context of coastal wetland conversion in estuary areas
Artificial intelligence, T-shaped teams, and risk management post COVID-19 and beyond
No full textWe explores the opportunity to apply Artificial Intelligence (AI) and T-Shaped Teams in risk management post the COVID-19 crisis and beyond. First, the study describes the three stages of AI adoption and the interest in AI before and during the COVID-19 pandemic. Second, the importance of AI in risk management is assessed based on the analysis of the performance of AI-implemented firms. Third, the roles of workforce, especially T-Shaped teams, in adopting AI at the firm level are highlighted. The new Technology, Innovation, and In-practice functions of the T-shaped teams are discussed with the opportunities and challenges when building a T-shaped team and adopting AI in enterprises. Next, a guide on building T-shaped Teams for risk management using AI is developed with the flexibility to implement in a wide range of corporates. The study concludes with future direction on risk management strategies to respond to new risks and make better business decisions to address shocks in the economy
Impacts of risk preference and social insurance on household financial market participation in China: Are there differences between urban and rural residents?
No full textThis letter examines the impact of risk preference and social insurance on household financial market participation and diversification using the 2017 and 2019 China Household Finance Survey. A multi-value treatment model is used to address the selection bias between risk preference and household financial investment, considering the moderation role of social insurance in between. Overall, our results show that high-risk takers are more likely to participate in the financial market and diversify their portfolios than low risk takers. Focusing on rural and urban differentials, we find marked differences in the impacts of risk preference and social insurance on household financial investment. Having social insurance may widen the difference in investment decisions between high- and low-risk takers in urban areas; the latter group tends not to participate in or diversify when socially insured. In contrast, having social insurance encourages low- and intermediate-risk preferred rural households to participate in the financial market and diversify their financial portfolios. Our work highlights the different consequences of social insurance on investment incentives of the rural and urban households. Whilst the obvious benefits of having social insurance for rural households via risk-sharing, there is undesired consequence of incentive distortion of urban households
Elephantopus scaber L. polysaccharides alleviate heat stress-induced systemic inflammation in mice via modulation of characteristic gut microbiota and metabolites
No full textElephantopus scaber L. (ESL) is a Chinese herb that is used both as a food and medicine, often being added to soups in summer in south China to relieve heat stress (HS), but its exact mechanism of action is unknown. In this study, heat-stressed mice were gavaged with ESL polysaccharides (ESLP) at 0, 150, 300, and 450 mg/kg/d‾¹ (n = 5) for seven days. The gut microbiota composition, short-chain fatty acids (SCFAs), seven neurotransmitters in faeces, expression of intestinal epithelial tight junction (TJ) proteins (Claudin-1, Occludin), and serum inflammatory cytokines were measured. The low dose of ESLP (ESLL) improved the adverse physiological conditions; significantly reduced the cytokines (TNF-α, IL-1β, IL-6) and lipopolysaccharide (LPS) levels (p < 0.05); upregulated the expression of Claudin-1; restored the gut microbiota composition including Achromobacter and Oscillospira, which were at similar levels to those in the normal control group; significantly increased beneficial SCFAs like butyric acid and 5-HT levels in the faeces of heat-stressed mice; and significantly decreased the valeric acid and glutamic acid level. The level of inflammatory markers significantly correlated with the above-mentioned indicators (p < 0.05). Thus, ESLL reduced the HS-induced systemic inflammation by optimizing gut microbiota (Achromobacter, Oscillospira) abundance, increasing gut beneficial SCFAs like butyric acid and 5-HT levels, and reducing gut valeric and glutamic acid levels