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X-ray digital radiography plays a pivotal role in accessing the internal structure of objects. Nevertheless, key imaging parameters, such as source-to-target distance or number of projected images needed for three-dimensional construction, mostly rely on real-life trials thus increasing radiation exposure risks. This paper introduces a recently developed software platform known as GMAX (Geant4-based Monte Carlo Advanced X-ray) that helps addressing above issues from a simulation perspective. GMAX employs Geant4, a Monte Carlo simulation code at its core and facilitates high-fidelity X-ray imaging, requiring no prior user experience. Compared to CAD models that only reflect object's geometrical information, GMAX simulates how objects interact with photon and can accurately evaluate important imaging parameters, such as target object to detector distance. It also provides three-dimensional construction functionality for images and therefore could be used as an effective tool for X-ray non-destructive testing and inspection. • GMAX simulates X-ray imaging process. • GMAX can help select best imaging parameters, such as target-to-detector distance. • GMAX can perform three-dimensional reconstruction using a small number of images. [ABSTRACT FROM AUTHOR]

Gastrointestinal mucositis is one of the most debilitating side effects of the chemotherapeutic agent irinotecan (CPT-11). Andrographolide, a natural bicyclic diterpenoid lactone, has been reported to possess anti-colitis activity. In this study, andrographolide treatment was found to significantly relieve CPT-11-induced colitis in tumor-bearing mice without decreasing the tumor suppression effect of CPT-11. CPT-11 causes DNA damage and the release of double-stranded DNA (dsDNA) from the intestine, leading to cyclic-GMP-AMP synthase (cGAS)‒stimulator of interferon genes (STING)-mediated colitis, which was significantly decreased by andrographolide both in vivo and in vitro. Mechanistic studies revealed that andrographolide could promote homologous recombination (HR) repair and downregulate dsDNA‒cGAS‒STING signaling and contribute to the improvement of CPT-11-induced gastrointestinal mucositis. These results suggest that andrographolide may be a novel agent to relieve gastrointestinal mucositis caused by CPT-11. Andrographolide could accelerate HR repair of DNA damage-induced by elevating expression of RAD51 and downregulate cGAS‒STING, thereby improving mucosal damage. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The BmELP protein was determined to interact with Bmtutl-519. • BmELP may play an important role in the growth and division of silkworm cells. • N. bombycis infection caused the up-regulation of BmELP expression level, especially in vitro. • BmELP played a role in the process of coping with pathogen invasion. The Turtle protein could act as a signaling receptor or function as a membrane-bound ligand for an unknown receptor. Alternatively, the Turtle protein could function as a co-receptor in a multi-protein receptor complex. Earlier work on the function of Bmtutl-519 suggested that it may act as a cell surface receptor or as a regulatory factor in the infection process of Nosema bombycis. To further investigate the function of Bmtutl-519 in the process of microsporidian infection and the possible regulatory pathways involved, we performed yeast two-hybrid screening on a silkworm midgut cDNA library and identified a Bombyx mori extensin-like protein/BmELP as a binding partner of Bmtutl-519. The interaction between Bmtutl-519 and BmELP was verified by GST pull-down and co-immunoprecipitation assays. Quantitative RT-PCR analysis showed that BmELP was commonly expressed in all of the examined tissues of the silkworm, and the expression was highest in the head. Moreover, BmELP was expressed throughout the entire development period, and the lowest levels of expression were observed at the egg stage. The results of infection experiments showed that N. bombycis infection caused the up-regulation of BmELP expression, especially in vitro. Taken together, our findings may provide new insights into the roles of BmELP and Bmtutl-519 in microsporidian infection. [ABSTRACT FROM AUTHOR]

Wireless and precise stimulation of deep brain structures could have important applications to study intact brain circuits and treat neurological disorders. Herein, we report that magnetoelectric nanoparticles (MENs) can be guided to a targeted brain region to stimulate brain activity with a magnetic field. We demonstrated the nanoparticles' capability to reliably evoke fast neuronal responses in cortical slices ex vivo. After fluorescently labeled MENs were intravenously injected and delivered to a targeted brain region by applying a magnetic field gradient, a magnetic field of low intensity (350–450 Oe) applied to the mouse head reliably evoked cortical activities, as revealed by two-photon and mesoscopic imaging of calcium signals and by an increased number of c-Fos expressing cells after stimulation. Neither brain delivery of MENs nor the magnetic stimulation caused significant increases in astrocytes and microglia. Thus, MENs could enable a non-invasive and contactless deep brain stimulation without the need of genetic manipulation. [ABSTRACT FROM AUTHOR]

Meretrix meretrix (M. meretrix) are commonly found on tidal flats along the global coastlines. They are believed to potentially affect the sedimentary processes and thus morphological dynamics on the tidal flat. Their effects on sediment erosion and deposition, however, are not well quantitatively understood. To fill this gap, we conducted an integrated synchronous field investigation of hydrodynamic, sediment properties, and macrobenthos at two nearby tidal flats, one with abundant M. meretrix and the other without. In addition, seasonal comparison between summer and winter for the M. meretrix abundant site, where there was much less M. meretrix in winter than in summer, was conducted to further examine the influence of M. meretrix on critical value for the initiation of sediment entrainment. The results show that the critical shear stress for erosion (τ e) in the M. meretrix abundant site was lower than the bare tidal flat by ~23%. Differently, for the critical shear stress for deposition (τ d), the value at the M. meretrix abundant site was greater than that at the bare tidal flat by ~30%. Overall, we concluded that the existence of M. meretrix tends to enhance both the erodibility of the sea bed and the deposition of suspended sediment in the water column. It is suggested that the effect of macrobenthos on sediment erosion/deposition should not be neglected when predicting long-term morphological changes of an intertidal flat. [ABSTRACT FROM AUTHOR]

The relationship between the properties and substrates of graphene is important to research the graphene synthesized by a bottom-up approach. Here, we synthesized graphene with a surface segregation method and demonstrated that a quadrilateral graphene was formed by using Ni(110) as a substrate. Most of the graphene edges were parallel to the [101] or [100] directions of Ni(110). We found that sulfur impurities in Ni that segregated to the surface with a C(2 × 2) surface reconstruction during the graphene growth played critical roles in the formation of the quadrilateral graphene flakes. Image 1 [ABSTRACT FROM AUTHOR]

In this paper, three La 1.89 Ce 0.11 CuO 4-x (LCCO) photosensitive sols were prepared with benzoylacetone (BzAcH), acetylacetone (AcAc) or 2,2′-bipyridine (BPY) as the chemical modifiers. UV absorption spectroscopy was employed to analyze the chelation mechanism of three chemical modifiers and metal ions in the sols. It has been found that the copper ions chelated with the chemical modifiers mentioned above and endowed ultraviolet photosensitivity to the sol, whereas the lanthanum ions and cerium ions did not chelate with the chemical modifiers. UV irradiation experiments indicated that the chelate compounds were decomposed and the decomposition products greatly reduced the solubility of LCCO gel films in the organic solvent. The LCCO films with fine structure were fabricated by using self-photosensitive property of the three gel films. The micro-machining process showed that LCCO fine patterns, prepared by the sol of BzAcH as the chemical modifiers, exhibited the highest precision and the minimum size of the prepared patterns reached to micron level. XRD patterns seen that the addition of chemical modifiers had no effect on the structure of LCCO inorganic film. R-T curve tests of fine-patterned LCCO films prepared with the above three sols revealed that the micro-machining method was a simple and cost-effective process, which did not influence the electrical properties of the LCCO films. [ABSTRACT FROM AUTHOR]