Reproductive period and preclinical cerebrospinal fluid markers for Alzheimer disease: a 25-year study

OBJECTIVE: The aim of the study was to examine the association between reproductive period, as an indicator of endogenous estrogen, and levels of cerebrospinal fluid (CSF) biomarkers for Alzheimer disease (AD). METHODS: A population-based sample of women from Gothenburg, Sweden was followed from 1968 to 1994 (N = 75). All women had natural menopause and were free from dementia. Information on reproductive period (age at menarche to age at menopause) was obtained from interviews from 1968 to 1980. Lumbar puncture was performed from 1992 to 1994 and CSF levels of Aβ42, Aβ40, P-tau, and T-tau were measured with immunochemical methods. Linear regression models adjusted for potential confounders were used to analyze the relationship between reproductive period and CSF biomarkers for AD. RESULTS: Longer reproductive period was associated with lower levels of Aβ42 (β = -19.2, P  = 0.01), higher levels of P-tau (β = 0.03, P  = 0.01), and lower ratio of Aβ42/Aβ40 (β = -0.02, P  = 0.01), while no association was observed for T-tau (β = 0.01, P  = 0.46). In separate analyses, examining the different components of reproductive period, earlier age at menarche was associated higher levels of P-tau (β = -0.07, P  = 0.031) and lower ratio of Aβ42/Aβ40 (β = 0.05, P  = 0.021), whereas no association was observed with Aβ42 (β = 31.1, P  = 0.11) and T-tau (β = -0.001, P  = 0.98). Furthermore, no association was observed between age at menopause and CSF biomarkers for AD. CONCLUSIONS: Our findings suggest that longer exposure to endogenous estrogen may be associated with increased levels of AD biomarkers in the preclinical phase of AD. These findings, however, need to be confirmed in larger samples. / Video Summary: http://links.lww.com/MENO/A804

Three decades of climate mitigation: why haven't we bent the global emissions curve?

Despite three decades of political efforts and a wealth of research on the causes and catastrophic impacts of climate change, global carbon dioxide emissions have continued to rise and are 60% higher today than they were in 1990. Exploring this rise through nine thematic lenses—covering issues of climate governance, the fossil fuel industry, geopolitics, economics, mitigation modeling, energy systems, inequity, lifestyles, and social imaginaries—draws out multifaceted reasons for our collective failure to bend the global emissions curve. However, a common thread that emerges across the reviewed literature is the central role of power, manifest in many forms, from a dogmatic political-economic hegemony and influential vested interests to narrow techno-economic mindsets and ideologies of control. Synthesizing the various impediments to mitigation reveals how delivering on the commitments enshrined in the Paris Agreement now requires an urgent and unprecedented transformation away from today's carbon- and energy-intensive development paradigm

Nanoscale surface topography reshapes neuronal growth in culture

International audienceNeurons are sensitive to topographical cues provided either by in vivo or in vitro environments on the micrometric scale. We have explored the role of randomly distributed silicon nanopillars on primary hippocampal neurite elongation and axonal differentiation. We observed that neurons adhere on the upper part of nanopillars with a typical distance between adhesion points of about 500 nm. These neurons produce fewer neurites, elongate faster, and differentiate an axon earlier than those grown on flat silicon surfaces. Moreover, when confronted with a differential surface topography, neurons specify an axon preferentially on nanopillars. As a whole, these results highlight the influence of the physical environment in many aspects of neuronal growth

Multiphysics simulation explaining the behaviour of evaporation-driven nanoporous generators

Funding Information: The authors acknowledge the financial support from the Academy of Finland project 319018. L.H. and T.K. acknowledge funding from the Aalto ELEC doctoral school, and C.T. from the Vilho, Yrjö ja Kalle Väisälä Fund grant issued by the Finnish Academy of Arts and Sciences. T.K. acknowledges the support from the Walter Ahlström foundation. Further thanks go to Dr. Benjamin Wilson for the pycnometry measurements. The pycnometry was done using the Raw Materials research infrastructure by Aalto University School of Chemical Engineering, and other experimental work using the facilities and equipment of Micronova Nanofabrication Center. Finally, we acknowledge the computational resources provided by the Aalto Science-IT project. Funding Information: The authors acknowledge the financial support from the Academy of Finland project 319018. L.H. and T.K. acknowledge funding from the Aalto ELEC doctoral school, and C.T. from the Vilho, Yrj? ja Kalle V?is?l? Fund grant issued by the Finnish Academy of Arts and Sciences. T.K. acknowledges the support from the Walter Ahlstr?m foundation. Further thanks go to Dr. Benjamin Wilson for the pycnometry measurements. The pycnometry was done using the Raw Materials research infrastructure by Aalto University School of Chemical Engineering, and other experimental work using the facilities and equipment of Micronova Nanofabrication Center. Finally, we acknowledge the computational resources provided by the Aalto Science-IT project. Publisher Copyright: © 2022 The Author(s)Evaporation-induced electricity generation in porous nanomaterials has recently attracted considerable attention due to relatively high produced voltages and wide operating conditions. Here, we present a combined study of computational and experimental work exploiting finite-element method simulations to find the critical parameters influencing the performance of such generators. The simulated behaviour is found to agree with the experimental data within typical variation of the measurements. We find that the electrical power produced by the generator depends not only on the properties of the porous material, but also on the surrounding environment of the generator. Particularly, the pore size and geometry are found to have a significant influence on the output power, highlighting the importance of accurate characterization of the samples and careful control of the laboratory conditions when performing experimental work. Increasing the pore size from 5 to 20 nm improves the simulated output voltage from 0.12 to 0.47 V, while increasing the ambient humidity to 100% will prevent voltage generation completely. The obtained results can guide the future design of generators based on water evaporation induced capillary flow in a nanoporous carbon black film, leading to more efficient power production.Peer reviewe