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The model checker Uppaal is used to formally model and analyze parts of Zeroconf, a protocol for dynamic configuration of IPv4 link-local addresses that has been defined in RFC 3927 of the IETF. Our goal has been to construct a mo...
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The model checker Uppaal is used to formally model and analyze parts of Zeroconf, a protocol for dynamic configuration of IPv4 link-local addresses that has been defined in RFC 3927 of the IETF. Our goal has been to construct a model that (a) is easy to understand by engineers, (b) comes as close as possible to the informal text (for each transition in the model there should be a corresponding piece of text in the RFC), and (c) may serve as a basis for formal verification. Our modeling efforts revealed several errors (or at least ambiguities) in the RFC that no one else spotted before. We present two proofs of the mutual exclusion property for Zeroconf (for an arbitrary number of hosts and IP addresses): a manual, operational proof, and a proof that combines model checking with the application of a new abstraction relation that is compositional with respect to committed locations. The model checking problem has been solved using Uppaal and the abstractions have been checked by hand.
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The directional polarimetric camera (DPC), developed by Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Science, is a satellite sensor used to observe the polarization and directionality of the earth’s reflectanc...
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The directional polarimetric camera (DPC), developed by Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Science, is a satellite sensor used to observe the polarization and directionality of the earth’s reflectance. It acquires the two-dimensional image of the earth with a large field of view (118.74°) and a high spatial resolution (3.3 km) in 8 spectral bands. The first DPC was successfully launched onboard the GaoFen-5 satellite in May 2018, subject to the Chinese high-resolution earth observation program. In this paper, a set of systematic and complete pre-flight calibrations of the DPC are proposed to ensure the effective characterization for in-flight calibration, so as to ensure the accuracy of DPC measured radiation polarization data and the reliability of inversion results. Since the geometric calibration method of the DPC has been presented in an early companion paper [Appl. Opt. 59226 (2020)], this paper will not introduce it in detail. Instead, the geometric calibration results of each spectral band together with a discussion on the origin of differences between spectral bands are analyzed, and the error analysis of the method is conducted. The results of the DPC geometric calibration is that the residuals of all spectral bands are less than 0.1 pixel. For radiometric calibration, the radiometric models of non-polarized bands and polarized bands are derived in detail, respectively, and the specific calibration methods with error analysis, equipment, and main results with their related accuracies for each parameter of the radiometric models are described. To verify the accuracy of calibration parameters, a series of polarization detection accuracy verification experiments based on a non-polarized radiation source, a polarizing system, and a natural scene were carried out. The experimental results show that the maximum deviation of degree of polarization between the set values of the polarizing system and measured values of the DPC at the corresponding positions of four field of view angles of 0, 15, 30, and 45 degrees of each polarized spectral band is 0.009, 0.004, and 0.003, respectively. The average error in measuring the degree of polarization of a non-polarized light source by all pixels in the three polarized bands is 0.0043, 0.0046, and 0.0037, respectively. And the relative deviations of each field of view are within 0.020 when the DPC and CE318N simultaneously measure the DoLP of sky. All of these prove the effectiveness of the pre-flight calibration.
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We present the results of a ～250 square degrees CO mapping (+26°???l ???+50° and ?5°???b ???+5°) toward the Aquila Rift region at a spatial resolution of ～50'' and a grid spacing of 30''. The high dynamic range CO maps with ...
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We present the results of a ～250 square degrees CO mapping (+26°???l ???+50° and ?5°???b ???+5°) toward the Aquila Rift region at a spatial resolution of ～50'' and a grid spacing of 30''. The high dynamic range CO maps with a spectral resolution of ～0.2 km s~(?1) display highly structured molecular cloud (MC) morphologies with valuable velocity information, revealing complex spatial and dynamical features of the local molecular gas. In combination with the MWISP CO data and the Gaia DR2, distances of the main MC structures in the local ISM are well determined toward the Aquila Rift region. We find that the total MC mass within 1 kpc is about ?4.1?×?10~(5) in the whole region. In fact, the mass of the molecular gas is dominated by the W40 giant molecular cloud (GMC) at ～474 pc (～1.4?×?10~(5) ) and the GMC complex G036.0+01.0 at ～560–670 pc (～2.0?×?10~(5) ), while the MCs at ～220–260 pc have gas masses of ～10~(2)–10~(3) . Interestingly, an ～80 pc long filamentary MC G044.0–02.5 at a distance of ～404 pc shows a systematic velocity gradient along and perpendicular to the major axis of the filament. The H i gas with enhanced emission has similar spatial morphologies and velocity features compared to the corresponding CO structure, indicating that large-scale converging H i flows are probably responsible for the formation of the MC. Meanwhile, the long filamentary MC consists of many sub-filaments with lengths ranging from ～0.5 pc to several pc, as well as prevalent networks of filaments in other large-scale local MCs.
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Abstract Human CST (CTC1‐STN1‐TEN1) is a ssDNA‐binding complex that interacts with the replisome to aid in stalled fork rescue. We previously found that CST promotes telomere replication to maintain genomic integrity via G‐qua...
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Abstract Human CST (CTC1‐STN1‐TEN1) is a ssDNA‐binding complex that interacts with the replisome to aid in stalled fork rescue. We previously found that CST promotes telomere replication to maintain genomic integrity via G‐quadruplex (G4) resolution. However, the detailed mechanism by which CST resolves G4s in vivo and whether additional factors are involved remains unclear. Here, we identify RECQ4 as a novel CST‐interacting partner and show that RECQ4 can unwind G4 structures in vitro using a FRET assay. Moreover, G4s accumulate at the telomere after RECQ4 depletion, resulting in telomere dysfunction, including the formation of MTSs, SFEs, and TIFs, suggesting that RECQ4 is crucial for telomere integrity. Furthermore, CST is also required for RECQ4 telomere or chromatin localization in response to G4 stabilizers. RECQ4 is involved in preserving genomic stability by CST and RECQ4 disruption impairs restart of replication forks stalled by G4s. Overall, our findings highlight the essential roles of CST and RECQ4 in resolving G‐rich regions, where they collaborate to resolve G4‐induced replication deficiencies and maintain genomic homeostasis.
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In this paper, we carry out stochastic comparisons on extreme order statistics (i.e. smallest and largest order statistics) from dependent and heterogeneous samples following modified proportional hazard rates (MPHR) and modified ...
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In this paper, we carry out stochastic comparisons on extreme order statistics (i.e. smallest and largest order statistics) from dependent and heterogeneous samples following modified proportional hazard rates (MPHR) and modified proportional reversed hazard rates (MPRHR) models. We build the usual stochastic order for sample minimums and maximums, and the hazard rate order on minimums of sample and the reversed hazard rate order on maximums of sample are also derived, respectively. Finally, some examples are given to illustrate the theoretical results.
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The water cycle in the soil-plant-atmosphere continuum is an important element of
hydrological and ecological studies, and differences in the composition characteristics
of hydrogen and oxygen stable isotopes in different water ...
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The water cycle in the soil-plant-atmosphere continuum is an important element of
hydrological and ecological studies, and differences in the composition characteristics
of hydrogen and oxygen stable isotopes in different water bodies can indicate water
cycling processes. In this study, hydrogen and oxygen isotopes of precipitation, soil
water and plant water samples had been collected in the subalpine scrubland of the
Qilian Mountains from May to October 2019. The Craig-Gordon model, the isotopic
steady-state (ISS) assumption, the Keeling Plot model and the two-source mixing
model were used to analyse the stable isotope compositions of different water bodies,
the stable isotope characteristics of water vapour of soil evaporation and plant
transpiration and the variation of evapotranspiration in the SPAC of the subalpine
scrubland. The results showed that plant transpiration (F_T) contributed 87.28% and
86.95% to evapotranspiration and soil evaporation (F_E) contributed 12.72% and
13.05% to evapotranspiration in the growing season on semi-sunny and semi-shaded
aspects, respectively, indicating that evapotranspiration in the subalpine scrubland
mainly came from the transpiration of scrubland plants. In the early of the growing
season (May-June), due to the rapid expansion of plant leaves, the contribution of
transpiration to evapotranspiration was at a high level, which intensified transpiration
and led to a gradual increase of the transpiration contribution. In the middle of the
growing season (July–August), owing to better conditions of rain and heat that made
plants grow vigorously, plant transpiration made the highest contribution to evapo-transpiration
more than 90%, which caused to an overwhelming contribution of plant
transpiration to evapotranspiration. In the later of growing season (September to
October), the contribution of plant transpiration to evapotranspiration decreased significantly
while that of soil evaporation increased, which was because plant photosynthesis
and respiration gradually declined for losing their leaves of scrub plants and
the relative atmospheric humidity was lower.
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We present wide-field and high-sensitivity CO(1–0) molecular line observations toward the Cassiopeia region, using the 13.7 m millimeter telescope of the Purple Mountain Observatory. The CO observations reveal a large-scale highl...
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We present wide-field and high-sensitivity CO(1–0) molecular line observations toward the Cassiopeia region, using the 13.7 m millimeter telescope of the Purple Mountain Observatory. The CO observations reveal a large-scale highly filamentary molecular cloud within the Galactic region of 1320 ≥ l ≥ 1220 and ?10 ≤ b ≤ 30 and the velocity range from approximately +1 to +4 km s?1. The measured length of the large-scale filament, referred to as the Cassiopeia Filament, is ～390 pc. The observed properties of the Cassiopeia Filament, such as length, column density, and velocity gradient, are consistent with those synthetic large-scale filaments in the inter-arm regions. Based on its observed properties and location on the Galactic plane, we suggest that the Cassiopeia Filament is a spur of the Local arm, which is formed due to the galactic shear. The western end of the Cassiopeia Filament shows a giant arc-like molecular gas shell, which extends in the velocity range from roughly ?1 to +7 km s?1. Finger-like structures, with systematic velocity gradients, are detected in the shell. The CO kinematics suggest that the large shell is expanding at a velocity of ～6.5 km s?1. Both the shell and finger-like structures outline a giant bubble with a radius of ～16 pc, which is likely produced by the stellar wind from the progenitor star of a supernova remnant. The observed spectral line widths suggest that the whole Cassiopeia Filament was quiescent initially until its west part was blown by the stellar wind and became supersonically turbulent.
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The Mw 6.3 Yutian earthquake, occurred in northwestern Tibet on 25 June 2020, is one of the major events sequentially occurring in the region following the 2008 Mw 7.2, 2012 Mw 6.2, and 2014 Mw 6.9 earthquakes, and is of great sig...
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The Mw 6.3 Yutian earthquake, occurred in northwestern Tibet on 25 June 2020, is one of the major events sequentially occurring in the region following the 2008 Mw 7.2, 2012 Mw 6.2, and 2014 Mw 6.9 earthquakes, and is of great significance for studying the tectonic activity and assessing future seismic hazards in the region. In this study, we used Sentinel-1 Synthetic Aperture Radar images to retrieve co- and post-seismic deformation and to investigate the coseismic rupture behavior of the fault and the mechanisms of postseismic deformation. Based on the slip models of recent four nearby major earthquakes, we explored the local stress evolution, triggering mechanism of the 2020 event and future regional seismic hazards. Postseismic modeling reveals that afterslip on fault patches surrounding the ruptured co-seismic patches is the main mechanism responsible for the near-field deformation, with the poroelastic rebound relaxation only accounts for maximumly 25% of the ground displacement and limited impact on the overall deformation pattern. The Coulomb failure stress changes (ΔCFS) suggest that the 2020 Yutian earthquake was inhibited by the 2008 Mw 7.2 earthquake but facilitated by the 2012 Mw 6.2 and 2014 Mw 6.9 earthquakes, resulting in an overall ΔCFS with a large lateral gradient on the 2020 fault. Stress concentrations on nearby major faults indicate increasing chances of seismic hazards in the eastern section of the Altyn Tagh fault at 82.8°E, the western section of the Guozha Co fault at 81.5°E and the entire section of the Ashikule fault.
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Oral microbial dysbiosis contributes to the development of oral squamous cell carcinoma (OSCC). Numerous studies have focused on variations in the oral bacterial microbiota of patients with OSCC. However, similar studies on fungal...
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Oral microbial dysbiosis contributes to the development of oral squamous cell carcinoma (OSCC). Numerous studies have focused on variations in the oral bacterial microbiota of patients with OSCC. However, similar studies on fungal microbiota, another integral component of the oral microbiota, are scarce. Moreover, there is an evidence gap regarding the role that microecosystems play in different niches of the oral cavity at different stages of oral carcinogenesis. Here, we catalogued the microbial communities in the human oral cavity by profiling saliva, gingival plaque, and mucosal samples at different stages of oral carcinogenesis. We analyzed the oral bacteriome and mycobiome along the health-premalignancy-carcinoma sequence. Some species, including Prevotella intermedia , Porphyromonas endodontalis , Acremonium exuviarum , and Aspergillus fumigatus , were enriched, whereas others, such as Streptococcus salivarius subsp. salivarius , Scapharca broughtonii , Mortierella echinula , and Morchella septimelata , were depleted in OSCC. These findings suggest that an array of signature species, including bacteria and fungi, are closely associated with oral carcinogenesis. OSCC-associated diversity differences, species distinction, and functional alterations were most remarkable in mucosal samples, not in gingival plaque or saliva samples, suggesting an urgent need to define oral carcinogenesis-associated microbial dysbiosis based on the spatial microbiome. IMPORTANCE Abundant oral microorganisms constitute a complex microecosystem within the oral environment of the host, which plays a critical role in the adjustment of various physiological and pathological states of the oral cavity. In this study, we demonstrated that variations in the “core microbiome” may be used to predict carcinogenesis. In addition, sample data collected from multiple oral sites along the health-premalignancy-carcinoma sequence increase our understanding of the microecosystems of different oral niches and their specific changes during oral carcinogenesis. This work provides insight into the roles of bacteria and fungi in OSCC and may contribute to the development of early diagnostic assays and novel treatments.
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Background It is well accepted that both competitive endogenous RNAs (ceRNAs) and immune microenvironment exert crucial roles in the tumor prognosis. The present study aimed to find prognostic ceRNAs and immune cells in lung adeno...
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Background It is well accepted that both competitive endogenous RNAs (ceRNAs) and immune microenvironment exert crucial roles in the tumor prognosis. The present study aimed to find prognostic ceRNAs and immune cells in lung adenocarcinoma (LUAD). Materials and Methods More specifically, we explored the associations of crucial ceRNAs with the immune microenvironment. The Cancer Genome Atlas (TCGA) database was employed to obtain expression profiles of ceRNAs and clinical data. CIBERSORT was utilized to quantify the proportion of 22 immune cells in LUAD. Results We constructed two cox regression models based on crucial ceRNAs and immune cells to predict prognosis in LUAD. Subsequently, seven ceRNAs and seven immune cells were involved in prognostic models. We validated both predicted models via an independent cohort GSE72094. Interestingly, both predicted models proved that the longer patients were smoking, the higher risk scores would be obtained. We further investigated the relationships between seven genes and immune/stromal scores via the ESTIMATE algorithm. The results indicated that CDC14A and H1F0 expression were significantly related to stromal scores/immune scores in LUAD. Moreover, based on the result of the ceRNA model, single-sample gene set enrichment analysis (ssGSEA) suggested that differences in immune status were evident between high- and low-risk groups.
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