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Human FOXP3 + CD25 + CD4 + regulatory T cells (Tregs) are essential to the maintenance of immune homeostasis. Several genes are known to be important for murine Tregs, but for human Tregs the genes and underlying molecular networks controlling the suppressor function still largely remain unclear. Here, we describe a strategy to identify the key genes directly from an undirected correlation network which we reconstruct from a very high time‐resolution (HTR) transcriptome during the activation of human Tregs/CD4 + T‐effector cells. We show that a predicted top‐ranked new key gene PLAU (the plasminogen activator urokinase) is important for the suppressor function of both human and murine Tregs. Further analysis unveils that PLAU is particularly important for memory Tregs and that PLAU mediates Treg suppressor function via STAT5 and ERK signaling pathways. Our study demonstrates the potential for identifying novel key genes for complex dynamic biological processes using a network strategy based on HTR data, and reveals a critical role for PLAU in Treg suppressor function. Network‐based analysis of transcriptome dynamics during activation in two human T‐cell subpopulations identifies key regulators, and reveals that PLAU plays a critical role in both human and murine regulatory T‐cell function. Synopsis Network‐based analysis of transcriptome dynamics during activation in two human T‐cell subpopulations identifies key regulators, and reveals that PLAU plays a critical role in both human and murine regulatory T‐cell function. We construct a Treg‐specific correlation network from a high time‐resolution transcriptome of human Tregs versus CD4 + T effector cells measured during their very early activation process. We propose a queen bee‐surrounding principle to predict key candidate genes from the simplified undirected correlation network rather than an advanced directed transcription regulatory network. These potential key genes would have not been easily identified by a differential expression analysis. We show that the plasminogen activator urokinase (PLAU) is critical for suppressor function of both human and murine Tregs. We further demonstrate that PLAU is particularly important for memory Tregs and that PLAU mediates Treg suppressor function via STAT5 and ERK signaling pathways.

Ensuring information security has emerged as a paramount concern in contemporary human society. Substantial advancements in this regard can be achieved by leveraging photonic signals as the primary information carriers, utilizing photonic logical gates capable of wavelength tunability across various time and spatial domains. However, the challenge remains in the rational design of materials possessing space‐time‐color multiple‐resolution capabilities. In this work, a facile approach is proposed for crafting metal‐organic halides (MOHs) that offer space‐time‐color resolution. These MOHs integrate time‐resolved room temperature phosphorescence and color‐resolved excitation wavelength dependencies with both space‐resolved ex situ optical waveguides and in situ heterojunctions. Capitalizing on these multifaceted properties, MOHs‐based two‐dimensional (2D) optical waveguides and heterojunctions exhibit the ability to tune full‐color emissions across the spectra from blue to red, operating within different spatial and temporal scales. Therefore, this work introduces an effective methodology for engineering space‐time‐color resolved MOH microstructures, holding significant promise for the development of high‐density photonic logical devices. Luminescent metal‐organic halide (MOH) microcrystals (L‐CdCl2 and L‐CdI2) could serve as 2D full‐color optical waveguides that transmit photon signals with ex situ space‐time‐color triple resolution characteristics. Moreover, the dynamic manipulation of heterojunctions (MOH‐Cl@I and MOH‐I@Cl) can be achieved, which exhibit interesting in situ space‐time‐color triple resolution features to further develop advanced photonic logical gates.

We present the discovery of an as yet nonrepeating fast radio burst (FRB), FRB 20210117A, with the Australian Square Kilometre Array Pathfinder (ASKAP), as a part of the Commensal Real-time ASKAP Fast Transients Survey. The subarcsecond localization of the burst led to the identification of its host galaxy at z = 0.214(1). This redshift is much lower than what would be expected for a source dispersion measure (DM) of 729 pc cm−3, given typical contributions from the intergalactic medium and the host galaxy. Optical observations reveal the host to be a dwarf galaxy with little ongoing star formation—very different to the dwarf host galaxies of the known repeating FRBs 20121102A and 20190520B. We find an excess DM contribution from the host and attribute it to the FRB’s local environment. We do not find any radio emission from the FRB site or host galaxy. The low magnetized environment and the lack of a persistent radio source indicate that the FRB source is older than those found in other dwarf host galaxies, establishing the diversity of FRB sources in dwarf galaxy environments. We find our observations to be fully consistent with the “hypernebula” model, where the FRB is powered by an accretion jet from a hyperaccreting black hole. Finally, our high time resolution analysis reveals burst characteristics similar to those seen in repeating FRBs. We encourage follow-up observations of FRB 20210117A to establish any repeating nature.

Assisted reproductive technology (ART) has yielded vast amounts of information and knowledge on human embryonic development in vitro; however, still images provide limited data on dynamic changes in the developing embryos. Using our high-resolution time-lapse cinematography (hR-TLC) system, we were able to describe normal human embryonic development continuously from the fertilization process to the hatched blastocyst stage in detail. Our hR-TLC observation also showed the embryonic abnormality of a third polar body (PB)-like substance likely containing a small pronucleus being extruded and resulting in single-pronucleus (1PN) formation, while our molecular biological investigations suggested the possibility that some 1PN embryos could be diploid, carrying both maternal and paternal genomes. Furthermore, in some embryos the extruded third PB-like substance was eventually re-absorbed into the ooplasm resulting in the formation of an uneven-sized, two-PN zygote. In addition, other hR-TLC observations showed that cytokinetic failure was correlated with equal-sized, multi-nucleated blastomeres that were also observed in the embryo showing early initiation of compaction. Assessment combining our hR-TLC with molecular biological techniques enables a better understanding of embryonic development and potential improvements in ART outcomes.

Speciated particle-phase organic nitrates (pONs) were quantified using online chemical ionization MS during June and July of 2013 in rural Alabama as part of the Southern Oxidant and Aerosol Study. A large fraction of pONs is highly functionalized, possessing between six and eight oxygen atoms within each carbon number group, and is not the common first generation alkyl nitrates previously reported. Using calibrations for isoprene hydroxynitrates and the measured molecular compositions, we estimate that pONs account for 3% and 8% of total submicrometer organic aerosol mass, on average, during the day and night, respectively. Each of the isoprene- and monoterpenes-derived groups exhibited a strong diel trend consistent with the emission patterns of likely biogenic hydrocarbon precursors. An observationally constrained diel box model can replicate the observed pON assuming that pONs (i) are produced in the gas phase and rapidly establish gas–particle equilibrium and (ii) have a short particle-phase lifetime (∼2–4 h). Such dynamic behavior has significant implications for the production and phase partitioning of pONs, organic aerosol mass, and reactive nitrogen speciation in a forested environment.

JWST, despite not being designed to observe astrophysical phenomena that vary on rapid timescales, can be an unparalleled tool for such studies. If timing systematics can be controlled, JWST will be able to open up the subsecond infrared timescale regime. Rapid time-domain studies, such as lag measurements in accreting compact objects and solar system stellar occultations, require both precise interframe timing and knowing when a time series begins, down to an absolute accuracy significantly below 1 s. In this work, we present two long-duration observations of the deeply eclipsing double white dwarf system ZTF J153932.16+502738.8, which we use as a natural timing calibrator to measure the absolute timing accuracy of JWST's clock. From our two epochs, we measure an average clock accuracy of 0.12 ± 0.06 s, implying that JWST can be used for subsecond time-resolution studies down to the ∼100 ms level, a factor ∼5 improvement upon the prelaunch clock accuracy requirement. We also find an asymmetric eclipse profile in the F322W2 band, which we suggest has a physical origin.

To investigate the impact of temporal and spatial resolution of rainfall data on watershed flood simulation performance, the rainfall data from meteorological stations and the gridded rainfall data from meteorological forecasts for a rainfall event were adopted in this study. Interpolation methods were applied to generate rainfall processes with different spatial and temporal resolutions. A hydrodynamic model was employed to simulate the flow rates at various sections of the watershed under different rainfall scenarios. The results show that as the spatial and temporal resolutions decreased, the flood variation patterns at various sections remained consistent. Namely, the determination coefficient (R2) decreased, whereas the root means square error (RMSE) and mean absolute error (MAE) increased, and the errors in peak flow rates and the fluctuation amplitudes of the flow rates at the sections increased as well. Moreover, a decrease in temporal resolution led to a delay in the peak flow timing. Significant differences were observed between the simulation results generated from the two different rainfall datasets. The R2 values for the simulated flow rates at each section were all above 0.75 for the observed rainfall data, while 40% of the results based on meteorological forecast data were below 0.5. Overall, the simulation results using observed rainfall data outperformed those using meteorological forecast data. Through the comparative analysis of simulation results including the rainfall characteristic parameters such as the watershed-averaged precipitation (AVP) and the coefficient of variation (CV), it was found that AVP had a strong correlation with the peak flow and its increase or decrease directly affected the peak flow. On the contrary, CV showed a negative correlation with the peak flow.

Pixelated low-gain avalanche diodes (LGADs) can provide both precision spatial and temporal measurements for charged particle detection; however, electrical termination between the pixels yields a no-gain region, such that the active area or fill factor is not sufficient for small pixel sizes. Trench-isolated LGADs (TI-LGADs) are a strong candidate for solving the fill-factor problem, as the p-stop termination structure is replaced by isolated trenches etched in the silicon itself. In the TI-LGAD process, the p-stop termination structure, typical of LGADs, is replaced by isolating trenches etched in the silicon itself. This modification substantially reduces the size of the no-gain region, thus enabling the implementation of small pixels with an adequate fill factor value. In this article, a systematic characterization of the TI-RD50 production, the first of its kind entirely dedicated to the TI-LGAD technology, is presented. Designs are ranked according to their measured inter-pixel distance, and the time resolution is compared against the regular LGAD technology.

This study investigates the morphological classification and drifting rate measurement of the repeating fast radio burst (FRB) source FRB 20240114A using the Five-hundred-meter Aperture Spherical Telescope. Detected on 2024 January 14, FRB 20240114A exhibited an exceptionally high burst rate, revealing unique properties. Through observational campaigns over several months, we selected a data set comprising 3203 bursts (2109 burst clusters) during a continuous monitoring session (15,780 s) on 2024 March 12. Improving upon previous work, we clarify the definitions of sub-bursts, bursts, and burst clusters. Using an average dispersion measures of 529.2 pc cm−3, we classified the burst clusters into Downward Drifting, Upward Drifting, No Drifting, No Evidence for Drifting, Not-Clear, and Complex burst clusters. Among the 978 burst clusters that exhibit drifting behavior, 233 (23.82%) show upward drifting. Additionally, if 142 upward-drifting single-component burst clusters are excluded, upward-drifting double- and multicomponent burst clusters still account for 10.89% of the 836 burst clusters exhibiting drifting behavior, equating to 91 burst clusters. Furthermore, if only upward-drifting burst clusters with consecutive time intervals (or upward-drifting bursts) are considered, only nine bursts remain. Drifting rate comparisons with other physical quantities reveal that the drifting rate increases with peak frequency for single-component burst clusters with drifting behavior. Moreover, in single-component burst clusters, those with upward drifting exhibit smaller effective widths, bandwidths, and fluxes than their downward-drifting counterparts. A Kolmogorov–Smirnov test further indicates that upward-drifting burst clusters possess longer consecutive time intervals than downward-drifting ones, suggesting distinct underlying physical mechanisms.

This study aims to develop a stochastic method (SM_GSTR) for generating short-time (i.e., hourly) rainstorm events at all grids (named gridded rainstorm events) in a region. The proposed SM_GSTR model is developed by the non-normal correlated multivariate Monte Carlo simulation (MMCS) method with the statistical properties and spatiotemporal correlation structures of the four event-based gridded rainfall characteristics. The radar-based rainfall data on 20 typhoon events at 336 grids in a basin located in north Taiwan, Nankan River watershed, are used in the model development and demonstration. The results from the model demonstration indicate that the proposed SM_GSTR model can reproduce a great number of gridded rainfall characteristics, of which, the statistical properties in time and space have a good fit to those from the observations in association with the acceptable deviation; thus, it can reasonably emulate the behavior of the rain field in both time and space. It is expected that the resulting massive rainfall-induced disasters (e.g., inundation and landslide) from the physical-based numerical model with the simulated gridded rainstorms by the proposed SM_GSTR model can be applied to establish an alternative artificial intelligence (AI) model for effectively forecasting the hydrologic variables (e.g., runoff and water-level).