4 research outputs found
How do practitioners characterize land tenure security?
Improving land tenure security (LTS) is a significant challenge for sustainable development. The Sustainable Development Goals and other recent global initiatives have renewed and increased the need to improve LTS to address climate change, biodiversity loss, food security, poverty reduction, and other challenges. At the same time, policymakers are increasingly interested in evidence- based policies and decisions, creating urgency for practitioners and researchers to work together. Yet, incongruent characterizations of LTS (identifying the key components of LTS) by practitioners and researchers can limit collaboration and information flows necessary for research and effective policymaking. While there are systematic reviews of how LTS is characterized in the academic literature, no prior study has assessed how practitioners characterize LTS. We address this gap using data from 54 interviews of land tenure practitioners working in 10 countries of global importance for biodiversity and climate change mitigation. Practitioners characterize LTS as complex and multifaceted, and a majority of practitioners refer to de jure terms (e.g., titling) when characterizing it. Notably, in our data just one practitioner characterized LTS in terms of perceptions of the landholder, contrasting the recent emphasis in the academic literature on landholder perceptions in LTS characterizations. Researchers should be aware of incongruence in how LTS is characterized in the academic literature when engaging practitioners.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155485/1/csp2186.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155485/2/csp2186_am.pd
Assessing bulk carbonates as archives for seawater Li isotope ratios
Silicate weathering is a primary control on the carbon cycle and therefore long-term climate. Tracing silicate weathering in the geological record has been a challenge for decades, with a number of proxies proposed and their limits determined. Recently lithium isotopes in marine carbonates have emerged as a potential tracer. Bulk carbonates are increasingly being used as a Li isotope archive, though with limited tests thus far of the robustness of this approach in the modern ocean. As the bulk composition of marine pelagic carbonates has changed through time and geographically, assessing the fidelity of bulk carbonate as proxy carrier is fundamental. To address the impact of compositional variability in bulk carbonate on Li isotopes, we examine 27 Bahamian aragonitic bulk carbonates and 16 Atlantic largely calcitic core-top sediment samples. Two core-tops only have trace (<10 %) carbonate, and are analysed to test whether carbonates in such sections are still a viable archive. We selectively extract the exchangeable and carbonate fractions from the core-top samples. The exchangeable fraction contains ∼2 % of the total Li and has a fairly constant offset from seawater of 16.5 ± 0.8‰. When leaching silicate-containing carbonates, acetic acid buffered with sodium acetate appears a more robust method of solely attacking carbonates compared to dilute HCl, which may also liberate some silicate-bound Li. Carbonates from samples that do not contain aragonite have the isotopic fractionation of seawater of Δ7Liseawater-calcite = 6.1 ± 1.3‰ (2sd), which is not affected by latitude or the water depth the sample was deposited at. The pure aragonite bulk carbonates from the Bahamas have a fractionation of Δ7Liseawater-aragonite = 9.6 ± 0.6‰. A sediment sample from the Galician coast that mostly consists of quartz is highly offset from seawater by ∼20‰ and also has relatively high Li/Ca ratios. These high values are not due to leaching of silicate material directly (Al/Ca ratios are low). We interpret this addition via cation exchange of Li from silicate during recrystallisation. Overall bulk carbonates from the open ocean are a reliable archive of seawater δ7Li, but care must be taken with carbonate mineralogy and low-carbonate samples. Overall, therefore, any examination of the palaeo-seawater δ7Li record must be reproduced in different global settings (e.g. multiple global cores) before it can be considered robust
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Preconception consultations with Maternal Fetal Medicine for obese women: a retrospective chart review
Background: Obesity is associated with impaired fertility and pregnancy complications, and preconception weight loss may improve some of these outcomes. The purpose of this study was to evaluate the quality and effectiveness of Maternal Fetal Medicine (MFM) preconception consults for obese women. Methods: We performed a retrospective chart review examining 162 consults at an academic medical center from 2008 to 2014. The main outcome measures included consultation content – e.g. discussion of obesity-related pregnancy complications, screening for comorbidities, and referrals for weight loss interventions – and weight loss. Results: Screening for diabetes and hypertension occurred in 48% and 51% of consults, respectively. Discussion of obesity-related pregnancy complications was documented in 96% of consults. During follow-up (median 11 months), 27% of patients saw a nutritionist, 6% saw a provider for a medically supervised weight loss program, and 6% underwent bariatric surgery. The median weight change was a loss of 0.6% body weight. Conclusions: In this discovery cohort, a large proportion of MFM preconception consultations lacked appropriate screening for obesity-related comorbidities. While the vast majority of consultations included a discussion of potential pregnancy complications, relatively few patients achieved significant weight loss. More emphasis is needed on weight loss resources and delaying pregnancy to achieve weight loss goals