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Trichoderma bio-inoculants to enhance grass seed yield in fields affected by take-all disease
No full textTake-all, a serious soil-borne disease of wheat also occurs on several herbage grasses (perennial ryegrass, prairie grass and timothy) and grass weed species (ripgut brome and smooth brome). The disease can affect seed yields both quantitatively and qualitatively. Glasshouse and field experiments were conducted using selected Trichoderma bio-inoculant formulations on prairie grass (Bromus willdenowii) and perennial ryegrass (Lolium perenne) in soils infested with Gaeumannomyces graminis var. tritici (Ggt). In a glasshouse experiment Ggt sugnificantly reduced prairie grass seed yield by 16% by reducing the number of seeds per plant. In the presence of Ggt, Trichoderma atroviride isolates LU132, LU140 and LU584 added to the soil in a prill formulation increased paririe grass seed yield by 13-16%, compared to Ggt control by increasing seed number per plant. In the field, two different bio-inoculant formulations were used, prills drilled into a second year perennial ryegrass seed crop, and seed coating for a new crop. In general, root quality observations revealed lower infection and disease severity in soils containing Trichoderma which led to an 20% seed yield increase for the prill formulation and 4% increase for the seed treatment. These increased seed-yields were associated with a higher number of reproductive tillers and a small reduction in seed dressing losses. Seed-coating with Trichoderma bio-inoculants as a prophylactic practice to improve grass seed yields will be discussed
Intraparenchymal convection enhanced delivery of AAV in sheep to treat Mucopolysaccharidosis IIIC
No full textMucopolysaccharidosis IIIC (MPSIIIC) is one of four Sanfilippo diseases sharing clinical signs and symptoms of severe cognitive and later motor decline and shortened life span. Unlike most other lysosomal diseases the missing enzyme, heparan sulfate acetyl CoA: α-glucosaminide N-acetyltransferase (HGSNAT), is bound to the lysosomal membrane and thus cannot cross the blood-brain barrier or diffuse between cells. We have previously demonstrated behavioural, biochemical and pathological correction of this disease in the mouse model of MPSIIIC using an Adeno-Associated Vector (AAV) delivering recombinant human HGSNAT from two intraparenchymal injections into the brain using an AAV-2 derived AAV truetype (AAV-TT)
serotype with improved distribution over AAV9. Current AdenoAssociated Vector (AAV) gene therapy delivery routes are sub-optimal for effective neuronal delivery in the entire human brain, which is essential in diseases characterised by global neurological pathology such as Mucopolysaccharidosis (MPS) IIIC. We describe AAV delivery using Brainlab targeted catheters or Hamilton syringes for convection enhanced delivery (CED) in sheep, designed to reduce proximal vector expression and improve spread in intraparenchymal injections. Using AAV-GFP, we found that Brainlab cranial navigation is optimal for gene therapy, although Hamilton syringes gave improved distribution over catheters, despite higher doses and titres of vector used in catheter delivery. Intraparenchymal CED gives better distribution compared to intracerebroventricular delivery for the same vector dose. We demonstrate that we can effectively deliver functional HGSNAT enzyme in 24-37% of a 140g gyrencephalic sheep brain using AAV9-HGSNAT in only 3 injections in one hemisphere. AAV serotype may also be important, as AAVTT-GFP displayed moderately better transduction compared to AAV9-GFP but both serotypes almost exclusively transduced neurons via this route. In addition, the presence of pre-existing IgG antibodies in serum does not seem to affect AAV transduction in the brain. Despite variabilities in vector purification, volume and titre, we found the primary attribute for efficient brain delivery is catheter design. These data help to inform a future potential clinical trial for MPSIIIC
A geospatial modelling approach to assess the capability of high-country stations in delivering ecosystem services
Get PDFThe creation of more sustainable land use strategies is paramount to designing multifunctional agricultural landscapes that allow grasslands to continually deliver multiple ecosystem services. A mapping modelling approach would provide us with a tool for system diagnosis to better assess the value of a landscape and define place-based practices for designing more context-adjusted systems that are in synergy with the complexity of grasslands. To assess the potential capability of a high-country pastoral livestock production system in New Zealand in delivering ecosystem services, this work uses a geospatial model as a decision support tool to identify management practices that enhance grassland health. The model uses national, climatic, soil, and landcover data to assess the agricultural productivity, flood mitigation, C sequestration, erosion, and sediment delivery capacity of a case study high-country station in New Zealand. Model outcomes suggest that the station has the potential for increased agricultural productivity although varying spatially, a high flood mitigation capacity, a high capacity for C sequestration, a moderate risk of erosion, a capacity to reduce sediment delivery to streams, and overall, a low to moderate nitrogen and phosphorus accumulation. Output maps display a spatial visualisation of ecosystem services associated with the landscape topography, soil, and vegetation patterns that allow the identification of neglected areas and planning of best place-based management practices strategies to enhance the health of grasslands
Flow analysis and hydraulic performance of denitrifying bioreactors under different carbon dosing treatments
No full textDenitrifying bioreactors are an effective approach for removing nitrate from a variety of non-point wastewater sources, including agricultural tile drainage. However, compared to alternate mitigation approaches such as constructed wetlands, nitrate removal in bioreactors may decline with time and low temperature, resulting in poor long-term nitrate removal rates. To address the low nitrate removal rates in bioreactors, the addition of an external carbon source has been found to be an effective method for enhancing and maintaining nitrate removal rates. While carbon dosing has led to a significant improvement in nitrate removal, some of the possible adverse effects of carbon dosing, such as clogging and reduction in hydraulic efficiency, remain unknown and need to be investigated. Using observations from both field and mesocosm trials, we compared the hydraulic performance of bioreactors with and without carbon dosing. The pilot-scale field bioreactor (58 m³ total woodchip volume, 25 m³ saturated volume, referred to as field bioreactor in this work) treated drainage water from a paddock of a dairy farm. The bioreactor received an exogenous carbon dose of 8% methanol (v/v) at 10 mL min¯¹ and 5 mL min¯¹ in the 2020 and 2021 drainage seasons, respectively. The field bioreactor had a statistically higher hydraulic conductivity in 2018 when not carbon-dosed of 4601 m day¯¹ , reducing to 1600 m day¯¹ in 2021 which was the second year of carbon dosing. Field observations could not establish whether the addition of liquid carbon could affect the bioreactor's internal hydraulics performance, such as actual hydraulic retention time (AHRT), despite a significant decline in hydraulic conductivity in the field bioreactor. Separate experiments on replicated bioreactor mesocosms were conducted to investigate the effects of carbon dosing on the internal hydraulic parameters of bioreactors. These mesocosm bioreactors had previously been used to study the long-term effects of methanol dosing on bioreactor performance, such as nitrate removal under steady-state conditions. The mesocosm and field bioreactors shared some characteristics, such as the use of methanol as an external carbon source, but the mesocosm experiments were hydrologically controlled contrary to the field bioreactor's transient operating conditions. We found that methanol dosing in either carbon or nitrate limiting conditions had no significant effects (p-value >0.05) on internal hydraulic parameters (e.g., effective utilization of media) when compared to control bioreactors. The present study offers insight into the long-term hydraulic performance of bioreactors and may help develop small-footprint bioreactors that incorporate external carbon dosing
Disaster response: The COVID-19 pandemic and insider trading around the world
No full textThis paper investigates how corporate insiders respond to the initial COVID-19 outbreaks. Using comprehensive insider transaction data from 25 countries, we document a consistent pattern of insider selling during the month after the first COVID-19 case is confirmed in a given country. Insider selling during these disease outbreaks is less pronounced in countries with higher information disclosure requirements, higher public enforcement index, a more efficient judiciary system, and stronger investor protection. Furthermore, cultural differences and the stringency levels of government responses to the COVID-19 outbreaks help moderate insider panic selling when health disasters strike. The findings suggest that a transparent, reliable business system contributes to rebuilding investor trust and corporate resilience during crises
Seaweed supplementation for metabolic and cardiovascular health: A double-blind RCT in women with metabolic syndrome
No full textPurpose: The purpose of this 8-week double blind RCT was to investigate the effects of a seaweed capsule (2g/day) on chronic metabolic and cardiovascular profiles compared to a control (placebo) capsule. The seaweed was a New Zealand grown green macroalgae (Ulva sp. B) which has only been investigated in rat trials.
Methods: Criteria for participation was female adults over 18 y.o. with ≥2 indicators of metabolic syndrome (MS), including waist circumference greater >88 cm; fasting triglycerides ≥150 mg/dL, high density lipoprotein cholesterol 110 mg/dL. Forty-four participants (55 y.o. ±11, BMI 35.3 ±9.2, number of MS indicators 3.5 ± 1.0) self selected through online advertisements (23 in experimental group). Body composition, waist/hip ratio, brachial blood pressure, pulse wave velocity (applanation tonometry), central augmentation and pulse pressure (both at aorta), blood glucose, Haemoglobin A1c, and blood lipids were collected in a laboratory pre and post supplementation. In SPSS, a repeated measures ANOVA, with Bonferroni correction, was conducted to assess pre-post differences for groups.
Results/findings: A seaweed dosage variable (by body mass, n=19) was investigated through regression on the above health predictor variables after controlling for diet and exercise. Tests of between-subjects effects showed no significant group X time effect of the seaweed supplement, although there were beneficial trends. Seaweed dosage was predicted best by waist:hip ratio, HbA1c, systolic BP, LDL (p=.001, R² = .825).
Conclusions: A 2g seaweed dosage per day did not illicit significant differences. Future studies should address the limitation of this study, such as increasing the seaweed dosage overall, increasing the dosage with increased body mass, increasing the duration of dosage and increasing the sample size. Significant differences did not appear in this dataset as was found with improved body composition and lipids in a rat trial. With correct dosage, green seaweed may significantly lower the risk factors for chronic health condition and benefit those with metabolic syndrome
A review of polar tourism scholarship (1980-2023): An update
No full textPresentation given at the Workshop on Tourism and Risk in the Antarctic Region, University of Tasmania
War, pandemic, and stock performance: A case of artificial intelligence adopting firms
No full textFirm performance is affected by extreme events including war and pandemic. In 2020, the COVID-19 pandemic weakened the performance of stock markets worldwide. Two years later, on 24 February 2022, the Russia-Ukraine war started and took a toll on the world economy, pushed up inflation, and increased the risk of severe adverse outcomes. There is a growing number of studies on the severity of stock market responses to the pandemic and the war in different regions and economies. The enormous increase in economic uncertainty has taught business executives valuable lessons about digital transformation and innovation. The IBM Artificial Intelligence (AI) Adoption Index shows a steady increase in global adoption of AI. However, studies regarding the impacts of the war and pandemic on AI-adopting firms are relatively new and scant.
Using data of 231 AI-adopting firms worldwide in developed and emerging markets from January 2013 to April 2022, this paper examines how AI stocks respond to the COVID-19 pandemic and the Russia-Ukraine war. We employ the two-step system Generalized Method of Moments estimation of linear dynamic panel-data model estimation to estimate the firm, market, and extreme event effects on the AI stock performance. Understanding the impacts of different determinants on the success or failure of AI adoption will support firms and investors to manage risks and investment portfolios for sustainable performance.
The results show that AI stocks respond to different extreme events differently. The performance of AI-adopting firms is not severely affected by the COVID-19 pandemic. The impact of the Russia-Ukraine war is more severe than the impact of the COVID-19 pandemic. AI-adopting firms in developed markets outperform those in emerging markets when the war broke out. In emerging markets, large firms benefit more from adopting AI in business than small firms
Potted vines: Exploring the management effect of leaf area to fruit weight ratios on yield and quality
No full textThe concept of vine balance is attaining a functional equilibrium between the three essential grapevine sinks — fruit, shoots, and roots. This means that any manipulation of source-sink balance that alters competing sinks will influence the equilibrium of the plant. The leaf area to fruit weight ratio (LA:FW) is a key metric used for assessing balance between the vegetative and reproductive growth of the vine. This ratio indicates that the main source of carbohydrates supplied to the fruit derives from leaf photosynthesis. A leaf area of 0.8-1.5m² of leaf/kg of fruit is reported to be optimal in the field. An alternative measure is that to ripen a bunch a shoot requires 14 leaves. Thus, vines that are source limited (inadequate leaf area) or have a high yield and excessive sink demand, will potentially have inadequate carbohydrates to enable fruit to reach an optimum ripening. The outcome of this imbalance is grapes can be low in soluble solids concentration, lighter colour, and undeveloped flavours and aroma at harvest. Therefore, it is essential to define the right balance between the vegetative and productive relationship to increase yield as well as improving the biochemical composition of the grape, ultimately affecting the yield-quality seesaw
Race-day injuries reported by veterinarians in stewards' reports for the 2022 harness racing season
No full textRacehorse injuries are a primary concern for horse welfare and public perception of the racing industries. Most research globally has focussed on Thoroughbreds, particularly in terms of musculoskeletal injuries (MSI). Less is known about the incidence of injuries occurring in Standardbred horses. The aim of this study was to quantify the incidence of veterinary reported injuries on race-days in the 2022 harness racing season