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In this paper, we study the joint Laplace transform of the sticky Brownian motion on an interval, its occupation time at zero and its integrated process. The perturbation approach of Li and Zhou [The joint Laplace transforms for diffusion occupation times, Adv. Appl. Probab.45 (2013) 1049–1067] is adopted to convert the problem into the computation of three Laplace transforms, which is essentially equivalent to solving the associated differential equations with boundary conditions. We obtain the explicit expression for the joint Laplace transform in terms of the modified Bessel function and Airy functions. [ABSTRACT FROM AUTHOR]

Abstract Background Adaptive Radiotherapy aims to identify anatomical deviations during a radiotherapy course and modify the treatment plan to maintain treatment objectives. This requires regions of interest (ROIs) to be defined using the most recent imaging data. This study investigates the clinical utility of using deformable image registration (DIR) to automatically propagate ROIs. Methods Target (GTV) and organ-at-risk (OAR) ROIs were non-rigidly propagated from a planning CT scan to a per-treatment CT scan for 22 patients. Propagated ROIs were quantitatively compared with expert physician-drawn ROIs on the per-treatment scan using Dice scores and mean slicewise Hausdorff distances, and center of mass distances for GTVs. The propagated ROIs were qualitatively examined by experts and scored based on their clinical utility. Results Good agreement between the DIR-propagated ROIs and expert-drawn ROIs was observed based on the metrics used. 94% of all ROIs generated using DIR were scored as being clinically useful, requiring minimal or no edits. However, 27% (12/44) of the GTVs required major edits. Conclusion DIR was successfully used on 22 patients to propagate target and OAR structures for ART with good anatomical agreement for OARs. It is recommended that propagated target structures be thoroughly reviewed by the treating physician.

Severe haze in Beijing during February of 2020, corresponding to the pandemics of Covid-19, was ascribed to residential coal combustion, which is always air lean or of oxygen deficiency, for household heating in the rural areas around Beijing. In this study, a drop-tube furnace combustion system was employed, where five types of representative coal were burned under the conditions of three respective temperatures and an oxygen-deficient combustion condition to simulate different residential coal combustion regimes. The on-line number concentration distribution of particulate matters in flue gas emitted was obtained. By size-segregated particulate matters of PM 1 , PM 2.5 and PM 10 collected in a three-stage sampler during various coal burning, the mass of organic carbon (OC) and elemental carbon (EC) and optical properties of light-absorbing organic carbonaceous aerosol were measured extensively. The results indicated that high temperature encouraged the formation of sub-micron and ultra-micron particles. It was found that coal types had a great impact on the formation of EC aerosols, that is, the mass of EC decreased with increasing geological maturity. Besides, the formation of EC was also affected by temperature, that is, the lower the temperature was, the more EC components were generated. The optical properties of the aerosol particle extracted by methanol from PM 1 , PM 2.5 , and PM 10 were measured and explored. The high values of absorption Ångström exponent (AAE) and mass absorption efficiency at the wavelength of 365 nm (MAE 365) indicated the high wavelength-dependence characteristics and strong light absorbing abilities of brown carbon (BrC) from residential coal burning. AAE values from 1200 °C combustion emissions was observed to be diminishing with increasing fixed carbon to volatile matter ratio (FC/VM) and decreasing OC/(OC + EC). In addition, MAE 365 values from low-temperature combustion were higher. These findings help us better understand the role that household coal burning plays in global BrC emission and its harm on the environment and human health. Unlabelled Image • Emissions from insufficient coal combustion of different coal types and different temperatures were explored. • Formation of particulate matters was reduced under lower temperature. • Formation of elementary carbonaceous aerosols was sensitive to temperatures and coal types. • Brown carbon emissions from low-temperature insufficient coal combustion were more wavelength-dependent and light-absorbing. [ABSTRACT FROM AUTHOR]

According to sedimentary structure, petrology and sequence analysis from seven sections (S1–S7) across the West Ujimqin basin, the late Carboniferous to Permian sedimentary facies have been recognized and summarized as four sedimentary systems, i.e. the late Carboniferous-early Permian sedimentary system (SA) comprising the alluvial fan–delta–littoral facies, the late Carboniferous sedimentary system (SB) including the littoral facies–delta facies–platform margin facies, the early Permian sedimentary system (SC) characterized by delta front and prodelta facies, and the middle Permian sedimentary system (SD) with alternations of littoral and delta facies. According to the spatial and temporal distribution of the four sedimentary systems, the basin filling process can be divided into three stages. The first stage (324–290 Ma) is dominated by bidirectional terrigenous sediments containing the SA from alluvial fan to delta and littoral facies in the northwestern and the SB from littoral–delta to platform margin facies in the southern, respectively. The second stage (290–270 Ma) is characterized by delta front and prodelta facies of the SC marked by thick-bedded matrix-supported conglomerate, rapid accumulation of terrigenous sediments and volcanic debris, syn -sedimentary deformation and slump. The third stage (270–255 Ma) formed the SD with the alternations of littoral and delta facies, which is represented by complex terrigenous clasts and intra-basin carbonate. These shallow and proximal sedimentary systems from fan delta to littoral facies indicate that there was not oceanic sedimentary system in the eastern CAOB during the late Carboniferous to Permian except for some small red sea basins, which provides convictive evidence that the Paleo-Asian Ocean (PAO) had closed before the late Carboniferous. Detrital zircon dating reveals bidirectional provenances of the West Ujimqin basin, indicating that it was a limited basin between two uplifts, which implies presence of the late Paleozoic "basin and uplift" tectonic framework that developed on the eastern CAOB during the late Paleozoic. Unlabelled Image • The West Ujimqin basin contains four Carboniferous – Permian sedimentary systems. • The basin filling process is characterized by three stages and bidirectional provenance. • It formed in extension setting and was controlled by "basin and uplift" tectonics [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a serious neurodegenerative disease that is induced by hyperglycaemia. Oxidative stress, inflammation and endoplasmic reticulum (ER) stress are involved in the development of DR. Sulforaphane (SF) is widely found in cruciferous plants and has a protective effect against retinal neurodegeneration in diabetes, but the mechanism is unclear. In this study, we investigated the mechanism by which SF protects against photoreceptor degeneration in diabetes. In vivo, a mouse model of diabetes was established by streptozotocin (STZ) injection, and the mice were treated with/without SF. Electroretinography (ERG) and H&E staining were used to evaluate retinal function and morphology. In vitro, 661w cells were treated with AGEs with/without SF. Cell viability and apoptosis were analysed by CCK-8 assay and flow cytometry. The expression of proteins and genes was assessed by western blot and qRT-PCR. The amplitude of the a-wave was decreased and the morphology was changed in the diabetic mice, and these changes were delayed by SF treatment. The percentage of apoptotic cells was increased and the cell viability was decreased after the treatment of 661w cells with AGEs. Moreover, the expression of GRP78, Txnip and TNFα was increased, however, this increased expression was reversed by SF treatment via AMPK pathway activation. Taken together, these data show that SF can delay photoreceptor degeneration in diabetes, and the underlying mechanism is related to the inhibition of ER stress, inflammation and Txnip expression through the activation of the AMPK pathway. [ABSTRACT FROM AUTHOR]