Air quality negatively impacts agriculture, reducing the yield of staple food crops. While measured data on African ground-level ozone levels are scarce, experimental studies demonstrate the damaging impact of ozone on crops. Common beans (Phaseolus vulgaris), an ozone-sensitive crop, are widely grown in Uganda.
View Article and Find Full Text PDFConserving Earth's most rapidly changing biomes necessitates understanding biological consequences of altered climes. Past species- and taxa-level responses to warming environs include numerous concentrated extirpations at the southern peripheries of distributions during the late Pleistocene. Less clear are localized capacities of cold-adapted species to mitigate thermal challenges against warming temperatures, especially through proximate behavioral and physiological adjustments.
View Article and Find Full Text PDFSci Total Environ
January 2024
The interaction between nitrogen storage and translocation, senescence, and late phase photosynthesis is critical to the post-anthesis grain fill period in wheat, but ozone's effect on nitrogen dynamics within the wheat plant is not well understood. This study used solardomes to expose a widely grown elite spring wheat cultivar, cv. Skyfall, to four levels of ozone (30 ppb, 45 ppb, 70 ppb, 85 ppb) for 11 weeks, with two levels of nitrogen fertilization, 140 kg ha and 160 kg ha, the higher rate including an additional 20 kg N ha at anthesis.
View Article and Find Full Text PDFTropospheric ozone (O3 ) is a global air pollutant that adversely affects plant growth. Whereas the impacts of O3 have previously been examined for some tropical commodity crops, no information is available for the pantropical crop, banana (Musa spp.).
View Article and Find Full Text PDFExtreme weather events are increasing in frequency and magnitude with profound effects on ecosystem functioning. Further, there is now a greater likelihood that multiple extreme events are occurring within a single year. Here we investigated the effect of a single drought, flood or compound (flood + drought) extreme event on temperate grassland ecosystem processes in a field experiment.
View Article and Find Full Text PDFBackground: Free testosterone (FT) determination may be helpful in evaluating men suspected of testosterone deficiency especially in conditions with altered binding-protein concentrations. However, methods for measuring FT by equilibrium dialysis and reference intervals vary among laboratories.
Objective: To determine reference intervals for FT in healthy, nonobese men by age groups as well as in healthy young men, 19-39 years, using a standardized equilibrium dialysis procedure METHODS: We measured FT in 145 healthy, nonobese men, 19 years or older, using a standardized equilibrium dialysis method performed for 16-h at 37°C using undiluted serum and dialysis buffer that mimicked the ionic composition of human plasma.
Impacts of tropospheric ozone on sweet potato (Ipomoea batatas) are poorly understood despite being a staple food grown in locations deemed at risk from ozone pollution. Three varieties of sweet potato were exposed to ozone treatments (peaks of: 30 (Low), 80 (Medium), and 110 (High) ppb) using heated solardomes. Weekly measurements of stomatal conductance (gs) and chlorophyll content (CI) were used to determine physiological responses, along with final yield.
View Article and Find Full Text PDFEndocrinol Metab Clin North Am
March 2022
For hypogonadal men treated with testosterone, the goal is to ensure that benefits are optimized, risks are minimized, and any adverse effects are identified early and managed appropriately. This can best be achieved by careful patient selection, excluding men with contraindications and addressing any modifiable risk factors in those at increased risk. A standardized plan should be used for monitoring that includes evaluation of symptoms, side effects, adherence, and measurement of testosterone and hematocrit.
View Article and Find Full Text PDFWe search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection.
View Article and Find Full Text PDFTropospheric ozone can have a detrimental effect on vegetation, including reducing the quantity of crop yield. This study uses modelled ozone flux values (PODIAM; phytotoxic ozone dose above 3 nmol m s, parameterised for integrated assessment modelling) for 2015, together with species-specific flux-effect relationships, spatial data on production and growing season dates to quantify the impact of ozone on the production of common wheat (Triticum aestivum) and common beans (Phaseolus vulgaris) across Sub-Saharan Africa (SSA). A case study for South Africa was also done using detailed data per province.
View Article and Find Full Text PDFPurpose Of The Study: We explored potential predictive variables associated with outcomes using baseline clinical parameters of 500 hospitalised patients with COVID -19 in a single centre, UK.
Methods: Retrospective study collecting demographic and clinical characteristics of patients admitted at Southend University Hospital from 20th February to 7th May 2020.
Results: The mean age of the cohort admitted to hospital with Covid-19 was 69.
Objective: Longer life expectancy has resulted in people living with an increasing number of co-morbidities. The average individual with inflammatory arthritis has two co-morbidities, which contribute to higher mortality, poorer functional outcomes and increased health-care utilization and cost. A number of studies have investigated the prevalence of co-morbidities, whereas this study was designed to look at patient perspectives.
View Article and Find Full Text PDFThe sensitivity of photosynthesis to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial carbon cycle response to future climate change. Although thermal acclimation of photosynthesis under rising temperature has been reported in many tree species, whether tropospheric ozone (O ) affects the acclimation capacity remains unknown. In this study, temperature responses of photosynthesis (light-saturated rate of photosynthesis (A ), maximum rates of RuBP carboxylation (V ), and electron transport (J ) and dark respiration (R ) of Populus tremula exposed to ambient O (AO , maximum of 30 ppb) or elevated O (EO , maximum of 110 ppb) and ambient or elevated temperature (ambient +5°C) were investigated in solardomes.
View Article and Find Full Text PDFObjectives: The study sought to explore the knowledge, attitudes and perceptions of healthcare providers and health programme managers regarding the benefits, challenges and impact of international medical volunteers' clinical placements. Views on how to better improve the work of international medical volunteers and the volunteer organisation Voluntary Service Overseas (VSO) for the benefit of local communities were also explored.
Settings: Public healthcare facilities, VSO offices in Gulu and VSO offices in Kampala, Uganda.
Environ Sci Pollut Res Int
March 2021
New critical levels for ozone based on accumulated flux through stomata (phytotoxic ozone dose, POD), for temperate perennial grassland (semi-)natural vegetation, have been agreed for use within the Convention on Long-Range Transboundary Air Pollution. These were based on data from several experiments conducted under naturally fluctuating environmental conditions that were combined and analysed to give linear dose-response relationships. Dose-response functions and flux-based critical levels were derived based on biomass and flower number.
View Article and Find Full Text PDFTropospheric (ground-level) ozone is a harmful phytotoxic pollutant, and can have a negative impact on crop yield and quality in sensitive species. Ozone can also induce visible symptoms on leaves, appearing as tiny spots (stipples) between the veins on the upper leaf surface. There is little measured data on ozone concentrations in Africa and it can be labour-intensive and expensive to determine the direct impact of ozone on crop yield in the field.
View Article and Find Full Text PDFWe present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
October 2020
The potential to capture additional air pollutants by introducing more vegetation or changing existing short vegetation to woodland on first sight provides an attractive route for lowering urban pollution. Here, an atmospheric chemistry and transport model was run with a range of landcover scenarios to quantify pollutant removal by the existing total UK vegetation as well as the UK urban vegetation and to quantify the effect of large-scale urban tree planting on urban air pollution. UK vegetation as a whole reduces area (population)-weighted concentrations significantly, by 10% (9%) for PM, 30% (22%) for SO, 24% (19%) for NH and 15% (13%) for O, compared with a desert scenario.
View Article and Find Full Text PDFElevated tropospheric ozone concentrations induce adverse effects in plants. We reviewed how ozone affects (i) the composition and diversity of plant communities by affecting key physiological traits; (ii) foliar chemistry and the emission of volatiles, thereby affecting plant-plant competition, plant-insect interactions, and the composition of insect communities; and (iii) plant-soil-microbe interactions and the composition of soil communities by disrupting plant litterfall and altering root exudation, soil enzymatic activities, decomposition, and nutrient cycling. The community composition of soil microbes is consequently changed, and alpha diversity is often reduced.
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