33 research outputs found

    Urban European Methane Emission Characteristics and Insight from CH<sup>4</sup> Source Tracers:na

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    Mitigating greenhouse gas emissions is becoming more of a priority in order to slow and reduce positive anthropogenic feedback to climate warming. As a consequence, there has been an increasing interest in understanding urban methane (CH4) emissions around the world. Past research has shown that urban CH4 emissions are influenced by a city's natural gas distribution network (NGDN) and pipeline replacement plans. National inventory estimates for NGDNs are heavily based on population density and may not correctly represent the spatial distribution of high emission locations. Mobile measurement studies can help improve and validate emissions from the energy sector and serve as a tool for effective mitigation planning. Therefore, this research focuses on locating and quantifying urban CH4 emissions of Greater London and Bucharest Romania in comparison with other European cities surveyed around similar times. Also, highlighted are the applications and reliability of three commonly used source tracers, δ13CCH4, δ2HCH4, and C2H6:CH4, with an additional focus on the development of a new δ2HCH4 measurement system.Presented here are measurements and quantifications of urban CH4 emissions from a western European city (London, UK) and an eastern European city (Bucharest, Romania), which differ culturally, governmentally, and economically. Extensive mobile surveys were conducted from 2018 to 2019, measuring street-level CH4 mole fractions, ethane (C2H6), and analyzing δ13CCH4 and δ2HCH4 for source type attributions.A total of 969 leak indicators were confirmed in Bucharest, and 925 for London. Compared to other recently measured cities, both Bucharest (1832 tons CH4 yr-1) and London (~2220 tons CH4 yr-1) had greater city-wide emission rates than Paris, France, and Hamburg, Germany. Isotopes (δ13CCH4 &amp; δ2HCH4) and ethane-methane ratios (C2:C1) were used extensively in an attempt to identify emission sources of both cities. In Bucharest, C2:C1 and δ2HCH4 tracers showed the greatest emission dominance from wastewater (58%-63%), while less than half (32%– 42%) were fossil fuel, and 0-5% were pyrogenic. London source tracers indicated a dominance of fossil fuel δ13CCH4 signatures and C2:C1 ratios (86% to 91%), while 7%-14% was biogenic, and only 0% - 2% were pyrogenic. This research will help to guide local governments with emission compliance and to prioritize greenhouse gas mitigation strategies for urban areas. This includes the identification of emissions that can most readily be reduced, helping to achieve the Global Methane Pledge of reducing human-induced emissions 45% by 2030

    A study protocol for a pilot randomized controlled trial to evaluate the effectiveness of a gene-based nutrition and lifestyle recommendation for weight management among adults: the MyGeneMyDiet® study

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    IntroductionManaging nutrition and lifestyle practices, nutrition phenotypes, and the genome forms the foundation of precision nutrition. Precision nutrition focuses on metabolic variability among individuals, and one approach to achieving its goals is to integrate gene-based nutrition and lifestyle recommendations in nutrition practice. However, scientific evidence proving the effectiveness of such recommendations is limited. This study will examine whether providing nutrition and lifestyle recommendations based on individual genotype can lead to better weight loss, along with reduction in body mass index (BMI), waist circumference, and body fat percentage among overweight and obese adults.Methods and analysisA parallel group, single-blind, randomized controlled trial will be conducted. Sixty-two overweight/obese individuals aged 19–59 years old will be recruited. Participants will be randomly allocated to either the intervention (n = 31) or the control arm (n = 31). Participants in the intervention group will receive the MyGeneMyDiet® Recommendation for Weight Management, a gene-based nutrition and lifestyle recommendation that was developed based on existing evidence of the effects of FTO rs9939609 on body weight, BMI, and physical activity; UCP1 rs1800592 on calorie intake; and TCF7L2 rs7903146 on dietary fat intake. Participants in the control group will receive the standard recommendations for weight management. The primary outcomes will be the differences in weight, BMI, waist circumference, and body fat percentage between arms in both the active phase (6 months) and inactive phase (last 6 months) of the trial. Participants in both arms will be evaluated at baseline and in months 3, 6, 9, and 12.DiscussionTo the best of our knowledge, this will be the first gene-based intervention that will adopt a phase of intensive nutrition counseling, followed by a simulation of a free-living state to determine adherence to a gene-based recommendation. This study will contribute to the future implementation of precision nutrition interventions by providing evidence on the effectiveness of a gene-based nutrition and lifestyle recommendation for weight loss.Clinical trial registrationclinicaltrials.gov, identifier [NCT05098899]

    New contributions of measurements in Europe to the global inventory of the stable isotopic composition of methane

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    Recent climate change mitigation strategies rely on the reduction of methane (CH4) emissions. Carbon and hydrogen isotope ratio (δ13CCH4 and δ2HCH4) measurements can be used to distinguish sources and thus to understand the CH4 budget better. The CH4 emission estimates by models are sensitive to the isotopic signatures assigned to each source category, so it is important to provide representative estimates of the different CH4 source isotopic signatures worldwide. We present new measurements of isotope signatures of various, mainly anthropogenic, CH4 sources in Europe, which represent a substantial contribution to the global dataset of source isotopic measurements from the literature, especially for δ2HCH4. They improve the definition of δ13CCH4 from waste sources, and demonstrate the use of δ2HCH4 for fossil fuel source attribution. We combined our new measurements with the last published database of CH4 isotopic signatures and with additional literature, and present a new global database. We found that microbial sources are generally well characterised. The large variability in fossil fuel isotopic compositions requires particular care in the choice of weighting criteria for the calculation of a representative global value. The global dataset could be further improved by measurements from African, South American, and Asian countries, and more measurements from pyrogenic sources. We improved the source characterisation of CH4 emissions using stable isotopes and associated uncertainty, to be used in top-down studies. We emphasise that an appropriate use of the database requires the analysis of specific parameters in relation to source type and the region of interest. The final version of the European CH4 isotope database coupled with a global inventory of fossil and non-fossil δ13CCH4 and δ2HCH4 source signature measurements is available at 10.24416/UU01-YP43IN

    Robust estimation of bacterial cell count from optical density

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    Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

    Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

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    Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

    Advancing Biodiversity Conservation & Eco-Human Health : Enhancing Food Ingredient Diversity Through Meal Planning at the University of British Columbia

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    This century has seen the accelerated deterioration of the environment, climate, and agricultural and species diversity. These complications are interconnected, as damages to biodiversity are linked with a heavy reliance on the same few crops (e.g. monocultures) on a local and global level (Secretariat of the Convention on Biological Diversity, 2012; Durazzo, 2019). In British Columbia, recent effects from climate change have also gravely impacted local food supply chains, highlighting the importance of creating a resilient food system that simultaneously minimizes greenhouse gas (GHG) emissions. The interrelationship between species diversity, the environment, and climate highlight the importance of applying a systems-based approach to our aim of enhancing biodiversity and nutrition at UBC. As a result of growing concerns about these environmental problems, especially among youth who stand to be most affected, many actions are being initiated around the world to raise the quality of our ecosystems and diets while reducing GHG emissions. At the University of British Columbia (UBC) Vancouver, food systems already contribute to over 21% of GHG emissions on campus and over 31% for extended/indirect emissions related to commutes, business air travel, embodied carbon, waste, paper, and other materials/processes (UBC, 2021). Therefore, according to the Campus Action Plan (CAP) 2030, UBC is working through multiple strategies – such as creating Climate-Friendly Food System (CFFS) Procurement Guidelines and a Food Resilience and Climate Action Strategy – to reduce its emissions by 85% by 2030 (UBC, 2021). To support UBC in achieving these strategies, this project assessed the current ingredient variability within Open Kitchen (OK), a UBC first-year residence dining hall, and provided a data analysis of viable ingredient substitutions to enhance ingredient diversity, diet quality, and food system sustainability. The substitutes recommended prioritized foods that are grown in ways that prioritize food system sustainability, reduction of GHG emissions as well as water and land use footprint, human health, and a wider variety of food options for UBC’s diverse population. By working with UBC Food Services (UBCFS), UBC CFFS Action Team, the CAP 2030 team, and the Social Ecological Economic Development Studies (SEEDS) Sustainability Program, this project seeks to contribute to a resilient food system within UBC Vancouver by conducting a Community-Based Action Research (CBAR) project. CBAR principles are important to this project as we conducted interviews with UBCFS staff recognizing them as “equal partners in identifying the problem to be investigated, undertaking the research itself, developing and implementing the intervention, and measuring the outcomes” (Gullion & Tilton, 2020), which ensures that the changes we suggest are sustainable and achievable for UBCFS. Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report.”Land and Food Systems, Faculty ofUnreviewedUndergraduat

    Mapping Urban Methane Sources in Paris, France

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    International audienceMegacities, with their large and complex infrastructures, are significant sources of methane emissions. To develop a simple, low-cost methodology to quantify these globally important methane sources, this study focuses on mobile measurements of methane (CH 4) and its isotopic composition in Paris. Data collected between September 2018 to March 2019 resulted in 17 days of measurements, which provided spatial distribution of street-level methane mixing ratios, source type identification, and emission quantification. Consequently, 90 potential leaks were detected in Paris sorted into three leak categories: natural gas distribution network emissions (63%), sewage network emissions (33%), and emissions from heating furnaces of buildings (4%). The latter category has not previously been reported in urban methane studies. Accounting for the detectable emissions from the ground, the total estimated CH 4 emission rate of Paris was 5000 L/min (190 t/yr), with the largest contribution from gas leaks (56%). This ranks Paris as a city with medium CH 4 emissions. Two areas of clusters were found, where 22% and 56% of the total potential emissions of Paris were observed. Our findings suggest that the natural gas distribution network, the sewage system, and furnaces of buildings are ideal targets for street-level CH 4 emission reduction efforts for Paris

    CUDC907, a dual phosphoinositide-3 kinase/histone deacetylase inhibitor, promotes apoptosis of NF2 Schwannoma cells

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    Neurofibromatosis Type 2 (NF2) is a rare tumor disorder caused by pathogenic variants of the merlin tumor suppressor encoded by NF2 . Patients develop vestibular schwannomas (VS), peripheral schwannomas, meningiomas, and ependymomas. There are no approved drug therapies for NF2. Previous work identified phosphoinositide-3 kinase (PI3K) as a druggable target. Here we screened PI3K pathway inhibitors for efficacy in reducing viability of human schwannoma cells. The lead compound, CUDC907, a dual histone deacetylase (HDAC)/PI3K inhibitor, was further evaluated for its effects on isolated and nerve-grafted schwannoma model cells, and primary VS cells. CUDC907 (3 nM IG 50 ) reduced human merlin deficient Schwann cell (MD-SC) viability and was 5–100 fold selective for MD over WT-SCs. CUDC907 (10 nM) promoted cell cycle arrest and caspase-3/7 activation within 24 h in human MD-SCs. Western blots confirmed a dose-dependent increase in acetylated lysine and decreases in pAKT and YAP. CUDC907 decreased tumor growth rate by 44% in a 14-day treatment regimen, modulated phospho-target levels, and decreased YAP levels. In five primary VS, CUDC907 decreased viability, induced caspase-3/7 cleavage, and reduced YAP levels. Its efficacy correlated with basal phospho-HDAC2 levels. CUDC907 has cytotoxic activity in NF2 schwannoma models and primary VS cells and is a candidate for clinical trials
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