111 research outputs found
Recommended high performance telescope system design for the TianQin project
China is planning to construct a new space-borne gravitational-wave (GW)
observatory, the TianQin project, in which the spaceborne telescope is an
important component in laser interferometry. The telescope is aimed to transmit
laser beams between the spacecrafts for the measurement of the displacements
between proof-masses in long arms. The telescope should have ultra-small
wavefront deviation to minimize noise caused by pointing error, ultra-stable
structure to minimize optical path noise caused by temperature jitter,
ultra-high stray light suppression ability to eliminate background noise. In
this paper, we realize a telescope system design with ultra-stable structure as
well as ultra-low wavefront distortion for the space-based GW detection
mission. The design requirements demand extreme control of high image quality
and extraordinary stray light suppression ability. Based on the primary
aberration theory, the initial structure design of the mentioned four-mirror
optical system is explored. After optimization, the maximum RMS wavefront error
is less than lamda/300 over the full field of view (FOV), which meets the noise
budget on the telescope design. The stray light noise caused by the back
reflection of the telescope is also analyzed. The noise at the position of
optical bench is less than 10-10 of the transmitted power, satisfying the
requirements of space gravitational-wave detection. We believe that our design
can be a good candidate for TianQin project, and can also be a good guide for
the space telescope design in any other similar science project
Identification of immune-related genes contributing to the development of glioblastoma using weighted gene co-expression network analysis
Background: The tumor microenvironment (TME) of human glioblastoma (GBM) exhibits considerable immune cell infiltration, and such cell types have been shown to be widely involved in the development of GBM. Here, weighted correlation network analysis (WGCNA) was performed on publicly available datasets to identify immune-related molecules that may contribute to the progression of GBM and thus be exploited as potential therapeutic targets.
Methods: WGCNA was used to identify highly correlated gene clusters in Chinese Glioma Genome Atlas glioma dataset. Immune-related genes in significant modules were subsequently validated in the Cancer Genome Atlas (TCGA) and Rembrandt databases, and impact on GBM development was examined in migration and vascular mimicry assays in vitro and in an orthotopic xenograft model (GL261 luciferase-GFP cells) in mice.
Results: WGCNA yielded 14 significant modules, one of which (black) contained genes involved in immune response and extracellular matrix formation. The intersection of these genes with a GO immune-related gene set yielded 47 immune-related genes, five of which exhibited increased expression and association with worse prognosis in GBM. One of these genes, TREM1, was highly expressed in areas of pseudopalisading cells around necrosis and associated with other proteins induced in angiogenesis/hypoxia. In macrophages induced from THP1 cells, TREM1 expression levels were increased under hypoxic conditions and associated with markers of macrophage M2 polarization. TREM1 siRNA knockdown in induced macrophages reduced their ability to promote migration and vascular mimicry in GBM cells in vitro, and treatment of mice with LP-17 peptide, which blocks TREM1, inhibited growth of GL261 orthotopic xenografts. Finally, blocking the cytokine receptor for CSF1 in induced macrophages also impeded their potential to promote tumor migration and vascular mimicry in GBM cells.
Conclusions: Our results demonstrated that TREM1 could be used as a novel immunotherapy target for glioma patients.publishedVersio
In vivo assessment of supra-cervical fetal membrane by MRI 3D CISS: A preliminary study
In approximately 8% of term births and 33% of pre-term births, the fetal membrane (FM) ruptures before delivery
Cryogenic in-memory computing using tunable chiral edge states
Energy-efficient hardware implementation of machine learning algorithms for
quantum computation requires nonvolatile and electrically-programmable devices,
memristors, working at cryogenic temperatures that enable in-memory computing.
Magnetic topological insulators are promising candidates due to their tunable
magnetic order by electrical currents with high energy efficiency. Here, we
utilize magnetic topological insulators as memristors (termed magnetic
topological memristors) and introduce a chiral edge state-based cryogenic
in-memory computing scheme. On the one hand, the chiral edge state can be tuned
from left-handed to right-handed chirality through spin-momentum locked
topological surface current injection. On the other hand, the chiral edge state
exhibits giant and bipolar anomalous Hall resistance, which facilitates the
electrical readout. The memristive switching and reading of the chiral edge
state exhibit high energy efficiency, high stability, and low stochasticity. We
achieve high accuracy in a proof-of-concept classification task using four
magnetic topological memristors. Furthermore, our algorithm-level and
circuit-level simulations of large-scale neural networks based on magnetic
topological memristors demonstrate a software-level accuracy and lower energy
consumption for image recognition and quantum state preparation compared with
existing memristor technologies. Our results may inspire further topological
quantum physics-based novel computing schemes.Comment: 33 pages, 12 figure
Loss of COPZ1 induces NCOA4 mediated autophagy and ferroptosis in glioblastoma cell lines
Dysregulated iron metabolism is a hallmark of many cancers, including glioblastoma (GBM). However, its role in tumor progression remains unclear. Herein, we identified coatomer protein complex subunit zeta 1 (COPZ1) as a therapeutic target candidate which significantly dysregulated iron metabolism in GBM cells. Overexpression of COPZ1 was associated with increasing tumor grade and poor prognosis in glioma patients based on analysis of expression data from the publicly available database The Cancer Genome Atlas (P < 0.001). Protein levels of COPZ1 were significantly increased in GBM compared to non-neoplastic brain tissue samples in immunohistochemistry and western blot analysis. SiRNA knockdown of COPZ1 suppressed proliferation of U87MG, U251 and P3#GBM in vitro. Stable expression of a COPZ1 shRNA construct in U87MG inhibited tumor growth in vivo by ~60% relative to controls at day 21 after implantation (P < 0.001). Kaplan–Meier analysis of the survival data demonstrated that the overall survival of tumor bearing animals increased from 20.8 days (control) to 27.8 days (knockdown, P < 0.05). COPZ1 knockdown also led to the increase in nuclear receptor coactivator 4 (NCOA4), resulting in the degradation of ferritin, and a subsequent increase in the intracellular levels of ferrous iron and ultimately ferroptosis. These data demonstrate that COPZ1 is a critical mediator in iron metabolism. The COPZ1/NCOA4/FTH1 axis is therefore a novel therapeutic target for the treatment of human GBM.publishedVersio
- …