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The neutron emission of compressed capsules filled with fuels in inertial confinement fusion implosions can be measured by neutron imaging systems. Source reconstruction is an important method in coded-aperture imaging. In this paper, we use a combination algorithm to reconstruct the neutron source image. This method can improve the resolution and signal–noise ratio of the reconstructed image. In addition, the ray tracing method is used to obtain the point spread functions of the whole field of view (250 µm), and thus, the system response can be obtained. The edge gray interpolation method is used to restore the missing portion of incomplete coded images. The method can maintain a good performance when the missing-data angle is limited to less than 50°. [ABSTRACT FROM AUTHOR]

A high resolution microscope is designed for plasma hard X-ray (10–20 keV) imaging diagnosis. This system consists of two toroidal mirrors, which are nearly parallel, with an angle twice that of the grazing incidence angle and a plane mirror for spectral selection and correction of optical axis offset. The imaging characteristics of single toroidal mirror and double mirrors are analyzed in detail by the optical path function. The optical design, parameter optimization, image quality simulation and analysis of the microscope are carried out. The optimized hard X-ray microscope has a resolution better than 5 μ m at 1 mm object field of view. The experimental data shows that the variation of the resolution is smaller in the direction of incident angle decrease than that in the increasing direction. [ABSTRACT FROM AUTHOR]

Nowadays, hepatocellular carcinoma (HCC) is still a major threat to human health globally, with a disappointing prognosis. Regular monitoring of patients at high risk, utilizing abdominal ultrasonography combined with alpha‐fetoprotein (AFP) serum analysis, enables the early detection of potentially treatable tumors. However, the approach has limitations due to its lack of sensitivity. Meanwhile, the current standard procedure for obtaining a tumor biopsy in cases of HCC is invasive and lacks the ability to assess the dynamic progression of cancer or account for tumor heterogeneity. Hence, there is a pressing need to develop non‐invasive, highly sensitive biomarkers for HCC which can improve the accuracy of early diagnosis, assess treatment response and accurately predict the prognosis. In contrast to the conventional method of tissue biopsy, liquid biopsy offers a non‐invasive approach that can be readily repeated. As a liquid biopsy approach, the analysis of cell‐free DNA (cfDNA) offers real‐time insights that can accurately portray the tumor burden and provide a comprehensive depiction of the genetic profile associated with HCC. In this review, we present a comprehensive summary of the recent research findings pertaining to the significance and potential practicality of cfDNA analysis in the early detection and effective management of HCC. [ABSTRACT FROM AUTHOR]

Non‐platinum graphene‐based electrocatalysts are vital for low‐cost energy conversion by hydrogen fuel cell. However, high oxygen reduction reaction (ORR) overpotentials limit their efficiency and stability. Here, we propose a strategy to increase graphene Fermi level by graphene encapsulating a metal with lower work function than graphene, aiming to enhance the ORR activity of graphene‐based materials. As an example, Ag nanoparticles (function work, 4.2 eV) are embedded into N‐doped graphene (function work, 4.5 eV) (Ag@NG). The Ag@NG exhibits the ORR onset potential of 0.804 V and excellent stability over 10000 electrochemical cycles in acidic electrolyte. Spectroscopic analysis confirms Ag−N coordination bond as an efficient electron transfer route significantly benefiting upshift of graphene Fermi level that enhances the ORR activity and stability. Level up: The authors embedded the Ag, a low‐work‐function metal, as a strong electron donor, into N‐doped graphene. As a result of Ag−N interaction, the accelerated charge transfer at Ag@NG‐electrolyte interface would induce the upshift of Fermi level of graphene, which effectively reduces the barrier for electron injection from graphene into the oxygen‐containing species and improves ORR performance. [ABSTRACT FROM AUTHOR]

A novel microstrip-fed ultrawideband antenna with dual band-notched performance is proposed and fabricated. A pair of L-shaped slots is etched in the ground plane to obtain the notched function in the 3.3-4 GHz WiMAX band. An eccentric ring and a stub with an arc structure are designed for rejecting the 5-6 GHz WLAN band. The obtained results show that the designed antenna satisfies the voltage standing wave ratio requirement of less than 2.5 at the frequency range from 3 to 32 GHz, except the dual notched bands of 3.3-4 and 5-6 GHz. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:704-706, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25840 [ABSTRACT FROM AUTHOR]

Deuterium–tritium neutron yield has reached up to about 1013 at the 100 kJ-level laser facility, which makes measurement of neutron emission images possible with the neutron imaging system. There are two methods to collect neutron images from the scintillator array, optical fiber taper and the lens system. Here, we report a design of the lens system for the neutron imaging system at the 100 kJ-level laser facility. The lens system, which consists of a nine-element collecting lens, with a spatial resolution of 20 µm and a light-collection efficiency of 5.9% has been designed. [ABSTRACT FROM AUTHOR]

Background: Localization and resection of nonvisible, nonpalpable pulmonary nodules during video‐assisted thoracoscopic surgery is challenging. In this study we developed a surgical navigation puncture robot system in order to locate small pulmonary nodules before thoracoscopic surgery. Methods: Four pigs were divided into group A and group B and underwent positioning puncture with the aid of the robotic system. The pigs in group A breathed freely during the experiment, whilst mechanical ventilation was used on the pigs in group B. Results: Using the robotic system to locate nodules achieved good results. For group A, a total of nine simulated nodules were created and successfully localized. The mean positioning accuracy was 9.6 ± 4.9 mm (range, 3.2–17.4 mm), and the time required for system positioning was 7.1 ± 1.0 minutes (range, 5.6–8.2 minutes). For group B, a total of 23 simulated nodules were created and successfully localized. The mean positioning accuracy was 2.9 ± 1.5 mm (range, 0.7–5.9 mm), and the time required for system positioning was 7.8 ± 1.1 minutes (range, 6.3–9.7 minutes). Conclusions: The new method using a surgical navigation puncture robot system to locate small pulmonary nodules is feasible and safe, and its positioning accuracy is sufficient to meet clinical requirements. In addition, results indicated that breathing had a great influence on the positioning accuracy, mainly in the longitudinal direction. Our surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting. Key points: Significant findings of the study: A new method using a surgical navigation puncture robot system was developed to locate small pulmonary nodules before thoracoscopic surgery. The results indicated that this method can provide accurate localization and permit smaller and more precise resections. What this study adds: A surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting. [ABSTRACT FROM AUTHOR]

An ultraviolet Thomson-scattering system has been designed and implemented on the Shenguang-III laser facility, a 48-beam, 3ω (351 nm), 180 kJ-level laser driver for high energy density physics and inertial confinement fusion researches. The 4ω (263.3 nm) probe beam of the Thomson-scattering system is injected from the north pole (top) of the target chamber, with an assistant beam-pointing monitor to achieve high pointing accuracy. The Thomson-scattered light is collected by a double-Cassegrain optical transmission system, which provides an achromatic image over a wide wavelength range of 200–800 nm. A novel on-line alignment method is developed and applied to the diagnostic system, ensuring a volumetric positioning accuracy of ∼30 μm for the scattering volume. An online calibration is also conducted to provide the wavelength benchmark and the spectral resolution of the system. This Thomson-scattering system has been tested in a complicated experimental environment with gas-filled hohlraums, and a high-quality ion feature of the scattered light has been obtained. [ABSTRACT FROM AUTHOR]

3,3′-diindolylmethane (DIM) is a dimer compound converted from Indoly-3-carbinol that had been studied as promising chemo-preventive agent against breast cancer. In this study, we observed that proportion of CD133+Nanog+ subpopulation in MCF-7 cells was significantly increased after DIM administration with up-regulated AKT activity by using CyTOF assay. SPADE analysis revealed this stem-like subpopulation exhibited apoptosis-resistance property against DIM treatment. By combining with AKT inhibitor AZD5363, DIM induced CD133 expression could be suppressed. In addition, a combination treatment of MCF-7 and MDA-MB-231 breast cancer cells with DIM and AZD5363 showed synergistic decreases in cell proliferation and induced apoptosis. Furthermore, results from imaging flow cytometry suggested that FoxO3a nuclear localization and PUMA expression could be improved by combination of AZD5363 with DIM. Taken together, the above observations suggested that the combination of AZD5363 with DIM could be developed as potential therapy for breast cancer. [Display omitted] • CD133 + stem-like cells was increased after DIM administration in MCF-7 cells. • AKT inhibitor AZD5363 decreased DIM induced CD133 expression in MCF-7 cells. • AKT inhibitor AZD5363 increased DIM-induced apoptosis in MCF-7 cells. • AZD5363 increased foxo3a nuclear translocation in DIM treated MCF-7 cells. [ABSTRACT FROM AUTHOR]

A timber–lightweight−concrete (TLC) composite beam connected with a ductile connector in which the ductile connector is made of a stainless−steel bolt anchored with nuts at both ends was proposed. The push−out results and bending performance of the TLC composite specimens were investigated by experimental testing. The push−out results of the shear specimens show that shear–slip curves exhibit good ductility and that their failure can be attributed to bolt buckling accompanied by lightweight concrete cracking. Through the bending tests of ten TLC composite beams and two contrast (pure timber) beams, the effects of different bolt diameters on the strengthening effect of the TLC composite beams were studied. The results show that the TLC composite beams and contrast timber beams break on the timber fiber at the lowest edge of the TLC composite beam, and the failure mode is attributed to bending failure, whereas the bolt connectors and lightweight concrete have no obvious breakage; moreover, the ductile bolt connectors show a good connection performance until the TLC composite beams fail. The ultimate bearing capacities of the TLC composite beams increase 2.03–3.5 times compared to those of the contrast beams, while the mid-span maximum deformation decrease nearly doubled. [ABSTRACT FROM AUTHOR]

In laser driven hohlraums, laser beams on the same incident cone may have different beam and plasma conditions, causing beam-to-beam backscatter difference and subsequent azimuthal variations in the x-ray drive on the capsule. To elucidate the large variation of backscatter proportion from beam to beam in some gas-filled hohlraum shots on Shenguang-III, two 28.5° beams have been measured with the Stimulated Raman Scattering (SRS) time-resolved spectra. A bifurcated fiber is used to sample two beams and then coupled to a spectrometer and streak camera combination to reduce the cost. The SRS spectra, characterized by a broad wavelength, were further corrected considering the temporal distortion and intensity modulation caused by components along the light path. This measurement will improve the understanding of the beam propagation inside the hohlraum and related laser plasma instabilities. [ABSTRACT FROM AUTHOR]