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Human metaplastic breast cancers (MpBC) are a rare, aggressive subclass of triple-negative breast cancers. Here, the authors show over-expression of histone reader TRIM24 is sufficient to generate tumors with a molecular signature of metabolic dysfunction and EMT in a mouse model of human MpBC.

A non-pulse-leakage optical fiber pumped 100-kHz level high beam quality Nd:YVO4 picosecond amplifier has been developed. An 80 MHz, 11.5 ps mode-locked picosecond laser is used as the seed with single pulse energy of 1 nJ. By harnessing the double β-BaB2O4 (BBO) crystal Pockels cells in both the pulse picker and regenerative amplifier, the seed pulse leakage of the output is suppressed effectively with an adjustable repetition rate from 200 to 500 kHz. Through one stage traveling-wave amplifier, a maximum output power of 24.5 W is generated corresponding to the injected regenerative amplified power of 9.73 W at 500 kHz. The output pulse duration is 16.9 ps, and the beam quality factor M2 is measured to be 1.25 with near-field roundness higher than 99% at the full output power.

A non-pulse-leakage optical fiber pumped 100-kHz level high beam quality Nd:YVO4 picosecond amplifier has been developed. An 80 MHz, 11.5 ps mode-locked picosecond laser is used as the seed with single pulse energy of 1 nJ. By harnessing the double β-BaB2O4 (BBO) crystal Pockels cells in both the pulse picker and regenerative amplifier, the seed pulse leakage of the output is suppressed effectively with an adjustable repetition rate from 200 to 500 kHz. Through one stage traveling-wave amplifier, a maximum output power of 24.5 W is generated corresponding to the injected regenerative amplified power of 9.73 W at 500 kHz. The output pulse duration is 16.9 ps, and the beam quality factor M2 is measured to be 1.25 with near-field roundness higher than 99% at the full output power. [ABSTRACT FROM AUTHOR]

A broadband high-reflection (HR) coating was used to suppress the electric-field intensity (EFI) enhancement in artificial nodules with five different sizes. However, the finitie-difference time-domain simulations reflected that the nodules initiating from 1.0-µmSiO2 seeds showed abnormally stronger EFI enhancement, which is almost two times higher than the EFI enhancement of 1.0-µm SiO2 seeds in a quarter-wave HR coating. This was also confirmed by the laser-induced damage threshold measurement. Our previous model combining light focusing and light penetrating effects was carefully examined to check whether the hotspots in a nodule initiating from the 1.0-µm SiO2 seed were in the focal area or not. Although it was found that the focal length of the nodule decreased with reducing seed diameter, the hotspots in nodules initiating from a 1.0-µm SiO2 seed were still much shallower than the focal area. In the broadband HR coating, the standing-wave EFI profiles at different working angles were given, which showed that the standing-wave EFI at the hotspots region was not negligible. Some complex interference or diffraction may cause the light to arrive at the hotspots region in phase and result in strong EFI enhancement. More work is necessary to gain a deeper understanding of this phenomenon. [ABSTRACT FROM AUTHOR]

Based on field data, this study investigates responses of six pre-existing buildings to an adjacent 24.8–25.2 m deep subway station excavated by the covered semi-top-down method. During excavation of 1 m wide and 50.2–50.5 m deep slurry trenches for diaphragm wall panels (i.e., diaphragm walling), buildings on both shallow and deep foundations developed noticeable settlements up to 15 mm. Subsequent excavation of the upper 15.9–17.7 m thick soils inside the pit only incurred limited building settlements less than 10 mm, which contrasted sharply with remarkable displacements of the diaphragm wall and ground nearby. As excavation continued to the final level, buildings on strip footing, stiffened raft foundation, strip footing atop long piles, and short piled raft foundation settled dramatically up to 40 mm, but those on long piled raft foundation still were hardly displaced. Like diaphragm wall and ground, all buildings developed significant postexcavation settlements up to 34.5 mm. Eventually, intolerable settlements culminated in damage to buildings. Generally, diaphragm walling-induced building settlement was mainly affected by the distance between building and slurry trench, building width perpendicular to slurry trench, and building weight rather than foundation type; excavation-induced building settlement was predominantly governed by foundation type and the distance between building and pit. Rapid casting of rigid underground structures after completion of excavation was of paramount importance for controlling time-dependent building settlement. Inconsistent with assumptions in literature, building settlement development was not concurrent with ground settlement development. Final building settlements were comparable to ground settlements for shallow foundations but much smaller for short piled foundations; in spite of this inconsistency, both of them conformed to underlying ground settlement troughs. Numerical simulations disclose that progressive extension of the ground displacement zone below the building undermined foundation bearing capacity, and consequently, building settlement took place. Underpinning was effective to copy with an adverse effect on buildings from adjacent excavation; however, excessively extending pile length below the excavation base could only result in limited additional reduction in building settlement. Compared to underpinning, the way of minimizing the ground displacement zone by modifying the lateral deflection profile of the retaining wall could be a more cost-effective alternative without sacrificing pit performance. [ABSTRACT FROM AUTHOR]

Because greenfields available for new developments in congested urban areas are scarce in China, more and more excavations for building basements or other underground facilities (e.g., new metro lines, underground shopping malls, parking garages) have to be carried out in the close proximity of existing metro lines. To ensure project safety, it is essential to know potential adverse effects of excavations on adjacent metro lines in service. Until now, many studies have contributed to the cases of excavations overlying existing tunnels. In contrast, only a few were known for excavations parallel to adjacent existing tunnels.With regard to the responses of existing metro stations to adjacent excavations, few case studies were reported in the literature. Through an extensive field instrumentation program in combination of numerical simulations, this study examines the performance of an oversized deep excavation in stiff clayey deposits and the corresponding responses of the adjacent metro station and twin shield tunnels in service. Taking advantage of the adopted zoned-construction procedure, both wall deflections and ground settlements of this oversized pit were not as significant as those reported in the literature, even smaller than those of long and narrow metro station pits. Consequently, both deformations and displacements of the existing metro line were within acceptable limits, and no obvious structural damage was observed. Throughout the excavation, the two-level island-type metro station exhibited a good structural integrity, which settled uniformly along the transverse direction and tilted slightly along the longitudinal direction. As to the twin shield tunnel linings, the one located within the primary ground influence zone developed considerably larger settlements and deformations than the other one within the secondary influence zone. As a product of the lateral stress relief attributable to soil removal, the tunnel lining experienced apparent elongations in the horizontal direction. [ABSTRACT FROM AUTHOR]