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研究证实地球内核是“有纹理的” 快报文章
地球科学快报,2023年第14期
作者:  王晓晨
Microsoft Word(15Kb)  |  收藏  |  浏览/下载:552/0  |  提交时间:2023/07/24
earth's inner core  heterogeneity  
The environmental neighborhoods of cities and their spatial extent 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (7)
作者:  Llaguno-Munitxa, M.;  Bou-Zeid, E.
收藏  |  浏览/下载:7/0  |  提交时间:2020/08/18
urban environment  air quality  urban planning  sensor networks  spatial heterogeneity  
Single-chain heteropolymers transport protons selectively and rapidly 期刊论文
NATURE, 2020, 577 (7789) : 216-+
作者:  Jiang, Tao;  Hall, Aaron;  Eres, Marco;  Hemmatian, Zahra;  Qiao, Baofu;  Zhou, Yun;  Ruan, Zhiyuan;  Couse, Andrew D.;  Heller, William T.;  Huang, Haiyan;  de la Cruz, Monica Olvera;  Rolandi, Marco;  Xu, Ting
收藏  |  浏览/下载:9/0  |  提交时间:2020/07/03

Precise protein sequencing and folding are believed to generate the structure and chemical diversity of natural channels(1,2), both of which are essential to synthetically achieve proton transport performance comparable to that seen in natural systems. Geometrically defined channels have been fabricated using peptides, DNAs, carbon nanotubes, sequence-defined polymers and organic frameworks(3-13). However, none of these channels rivals the performance observed in their natural counterparts. Here we show that without forming an atomically structured channel, four-monomer-based random heteropolymers (RHPs)(14) can mimic membrane proteins and exhibit selective proton transport across lipid bilayers at a rate similar to those of natural proton channels. Statistical control over the monomer distribution in an RHP leads to segmental heterogeneity in hydrophobicity, which facilitates the insertion of single RHPs into the lipid bilayers. It also results in bilayer-spanning segments containing polar monomers that promote the formation of hydrogen-bonded chains(15,16) for proton transport. Our study demonstrates the importance of the adaptability that is enabled by statistical similarity among RHP chains and of the modularity provided by the chemical diversity of monomers, to achieve uniform behaviour in heterogeneous systems. Our results also validate statistical randomness as an unexplored approach to realize protein-like behaviour at the single-polymer-chain level in a predictable manner.


  
The single-cell pathology landscape of breast cancer 期刊论文
NATURE, 2020, 578 (7796) : 615-+
作者:  Fouda, Abdelrahman Y.
收藏  |  浏览/下载:25/0  |  提交时间:2020/07/03

Single-cell analyses have revealed extensive heterogeneity between and within human tumours(1-4), but complex single-cell phenotypes and their spatial context are not at present reflected in the histological stratification that is the foundation of many clinical decisions. Here we use imaging mass cytometry(5) to simultaneously quantify 35 biomarkers, resulting in 720 high-dimensional pathology images of tumour tissue from 352 patients with breast cancer, with long-term survival data available for 281 patients. Spatially resolved, single-cell analysis identified the phenotypes of tumour and stromal single cells, their organization and their heterogeneity, and enabled the cellular architecture of breast cancer tissue to be characterized on the basis of cellular composition and tissue organization. Our analysis reveals multicellular features of the tumour microenvironment and novel subgroups of breast cancer that are associated with distinct clinical outcomes. Thus, spatially resolved, single-cell analysis can characterize intratumour phenotypic heterogeneity in a disease-relevant manner, with the potential to inform patient-specific diagnosis.


A single-cell, spatially resolved analysis of breast cancer demonstrates the heterogeneity of tumour and stroma tissue and provides a more-detailed method of patient classification than the current histology-based system.


  
Hot moments in ecosystem fluxes: High GPP anomalies exert outsized influence on the carbon cycle and are differentially driven by moisture availability across biomes 期刊论文
ENVIRONMENTAL RESEARCH LETTERS, 2020, 15 (5)
作者:  Kannenberg, Steven A.;  Bowling, David R.;  Anderegg, William R. L.
收藏  |  浏览/下载:14/0  |  提交时间:2020/05/13
carbon uptake  eddy covariance  meteorological variability  temporal heterogeneity  
Deciphering human macrophage development at single-cell resolution 期刊论文
NATURE, 2020
作者:  Oberst, Polina;  Fievre, Sabine;  Baumann, Natalia;  Concetti, Cristina;  Bartolini, Giorgia;  Jabaudon, Denis
收藏  |  浏览/下载:20/0  |  提交时间:2020/07/03

Macrophages are the first cells of the nascent immune system to emerge during embryonic development. In mice, embryonic macrophages infiltrate developing organs, where they differentiate symbiotically into tissue-resident macrophages (TRMs)(1). However, our understanding of the origins and specialization of macrophages in human embryos is limited. Here we isolated CD45(+) haematopoietic cells from human embryos at Carnegie stages 11 to 23 and subjected them to transcriptomic profiling by single-cell RNA sequencing, followed by functional characterization of a population of CD45(+)CD34(+)CD44(+) yolk sac-derived myeloid-biased progenitors (YSMPs) by single-cell culture. We also mapped macrophage heterogeneity across multiple anatomical sites and identified diverse subsets, including various types of embryonic TRM (in the head, liver, lung and skin). We further traced the specification trajectories of TRMs from either yolk sac-derived primitive macrophages or YSMP-derived embryonic liver monocytes using both transcriptomic and developmental staging information, with a focus on microglia. Finally, we evaluated the molecular similarities between embryonic TRMs and their adult counterparts. Our data represent a comprehensive characterization of the spatiotemporal dynamics of early macrophage development during human embryogenesis, providing a reference for future studies of the development and function of human TRMs.


Single-cell RNA sequencing of haematopoietic cells from human embryos at different developmental stages sheds light on the development and specification of macrophages in different tissues.


  
Preferential Flow Enhances Pumping-Induced Saltwater Intrusion in Volcanic Aquifers 期刊论文
WATER RESOURCES RESEARCH, 2020, 56 (5)
作者:  Geng, Xiaolong;  Michael, Holly A.
收藏  |  浏览/下载:8/0  |  提交时间:2020/05/13
heterogeneity  volcanic aquifers  saltwater intrusion  nearshore pumping  conduits  coastal freshwater vulnerability  
Subcore Scale Fluid Flow Behavior in a Sandstone With Cataclastic Deformation Bands 期刊论文
WATER RESOURCES RESEARCH, 2020, 56 (4)
作者:  Romano, Carla R.;  Zahasky, Christopher;  Garing, Charlotte;  Minto, James M.;  Benson, Sally M.;  Shipton, Zoe K.;  Lunn, Rebecca J.
收藏  |  浏览/下载:7/0  |  提交时间:2020/07/02
deformation bands  multiphase fluid flow  capillary heterogeneity  X-ray computed tomography  positron emission tomography  
Lateral Variations of Shear-Wave Velocity in the D '' Layer Beneath the Indian-Eurasian Plate Collision Zone 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (6)
作者:  Li, Guohui;  Bai, Ling;  Ritsema, Jeroen
收藏  |  浏览/下载:6/0  |  提交时间:2020/07/02
D  Indian-Eurasian plate collision zone  3-D synthetic waveform  ScS and S phases  compositional heterogeneity  long-term subduction  
Mechanisms and therapeutic implications of hypermutation in gliomas 期刊论文
NATURE, 2020, 580 (7804) : 517-+
作者:  Feng, Kaibo;  Quevedo, Raundi E.;  Kohrt, Jeffrey T.;  Oderinde, Martins S.;  Reilly, Usa;  White, M. Christina
收藏  |  浏览/下载:26/0  |  提交时间:2020/07/03

A high tumour mutational burden (hypermutation) is observed in some gliomas(1-5)  however, the mechanisms by which hypermutation develops and whether it predicts the response to immunotherapy are poorly understood. Here we comprehensively analyse the molecular determinants of mutational burden and signatures in 10,294 gliomas. We delineate two main pathways to hypermutation: a de novo pathway associated with constitutional defects in DNA polymerase and mismatch repair (MMR) genes, and a more common post-treatment pathway, associated with acquired resistance driven by MMR defects in chemotherapy-sensitive gliomas that recur after treatment with the chemotherapy drug temozolomide. Experimentally, the mutational signature of post-treatment hypermutated gliomas was recapitulated by temozolomide-induced damage in cells with MMR deficiency. MMR-deficient gliomas were characterized by a lack of prominent T cell infiltrates, extensive intratumoral heterogeneity, poor patient survival and a low rate of response to PD-1 blockade. Moreover, although bulk analyses did not detect microsatellite instability in MMR-deficient gliomas, single-cell whole-genome sequencing analysis of post-treatment hypermutated glioma cells identified microsatellite mutations. These results show that chemotherapy can drive the acquisition of hypermutated populations without promoting a response to PD-1 blockade and supports the diagnostic use of mutational burden and signatures in cancer.


Temozolomide therapy seems to lead to mismatch repair deficiency and hypermutation in gliomas, but not to an increase in response to immunotherapy.