4,240 research outputs found
Structural and Functional Brain Remodeling during Pregnancy with Diffusion Tensor MRI and Resting-State Functional MRI
Although pregnancy-induced hormonal changes have been shown to alter the brain at the neuronal level, the exact effects of pregnancy on brain at the tissue level remain unclear. In this study, diffusion tensor imaging (DTI) and resting-state functional MRI (rsfMRI) were employed to investigate and document the effects of pregnancy on the structure and function of the brain tissues. Fifteen Sprague-Dawley female rats were longitudinally studied at three days before mating (baseline) and seventeen days after mating (G17). G17 is equivalent to the early stage of the third trimester in humans. Seven age-matched nulliparous female rats served as non-pregnant controls and were scanned at the same time-points. For DTI, diffusivity was found to generally increase in the whole brain during pregnancy, indicating structural changes at microscopic levels that facilitated water molecular movement. Regionally, mean diffusivity increased more pronouncedly in the dorsal hippocampus while fractional anisotropy in the dorsal dentate gyrus increased significantly during pregnancy. For rsfMRI, bilateral functional connectivity in the hippocampus increased significantly during pregnancy. Moreover, fractional anisotropy increase in the dentate gyrus appeared to correlate with the bilateral functional connectivity increase in the hippocampus. These findings revealed tissue structural modifications in the whole brain during pregnancy, and that the hippocampus was structurally and functionally remodeled in a more marked manner.published_or_final_versio
"Centralized or Decentralized?": Concerns and Value Judgments of Stakeholders in the Non-Fungible Tokens (NFTs) Market
Non-fungible tokens (NFTs) are decentralized digital tokens to represent the
unique ownership of items. Recently, NFTs have been gaining popularity and at
the same time bringing up issues, such as scams, racism, and sexism.
Decentralization, a key attribute of NFT, contributes to some of the issues
that are easier to regulate under centralized schemes, which are intentionally
left out of the NFT marketplace. In this work, we delved into this
centralization-decentralization dilemma in the NFT space through mixed
quantitative and qualitative methods. Centralization-decentralization dilemma
is the dilemma caused by the conflict between the slogan of decentralization
and the interests of stakeholders. We first analyzed over 30,000 NFT-related
tweets to obtain a high-level understanding of stakeholders' concerns in the
NFT space. We then interviewed 15 NFT stakeholders (both creators and
collectors) to obtain their in-depth insights into these concerns and potential
solutions. Our findings identify concerning issues among users: financial
scams, counterfeit NFTs, hacking, and unethical NFTs. We further reflected on
the centralization-decentralization dilemma drawing upon the perspectives of
the stakeholders in the interviews. Finally, we gave some inferences to solve
the centralization-decentralization dilemma in the NFT market and thought about
the future of NFT and decentralization.Comment: Accepted by CSCW 202
Accurate Liability Estimation Improves Power in Ascertained Case Control Studies
Linear mixed models (LMMs) have emerged as the method of choice for
confounded genome-wide association studies. However, the performance of LMMs in
non-randomly ascertained case-control studies deteriorates with increasing
sample size. We propose a framework called LEAP (Liability Estimator As a
Phenotype, https://github.com/omerwe/LEAP) that tests for association with
estimated latent values corresponding to severity of phenotype, and demonstrate
that this can lead to a substantial power increase
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