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Pancreatic cancer with less than 10% 3-year survival rate is one of deadliest cancer types and greatly benefits from enhanced radiotherapy. Organ motion monitoring helps spare the normal tissue from high radiation and, in turn, enables the dose escalation to the target that has been shown to improve the effectiveness of RT by doubling and tripling post-RT survival rate. The flexible array transducer is a novel and promising solution to address the limitation of conventional US probes. We proposed a novel shape estimation for flexible array transducer using two sequential algorithms: (i) an optical tracking-based system that uses the optical markers coordinates attached to the probe at specific positions to estimate the array shape in real-time and (ii) a fully automatic shape optimization algorithm that automatically searches for the optimal array shape that results in the highest quality reconstructed image. We conducted phantom and in vivo experiments to evaluate the estimated array shapes and the accuracy of reconstructed US images. The proposed method reconstructed US images with low full-width-at-half-maximum (FWHM) of the point scatters, correct aspect ratio of the cyst, and high-matching score with the ground truth. Our results demonstrated that the proposed methods reconstruct high-quality ultrasound images with significantly less defocusing and distortion compared with those without any correction. Specifically, the automatic optimization method reduced the array shape estimation error to less than half-wavelength of transmitted wave, resulting in a high-quality reconstructed image.

BACKGROUND: Qinxiang Qingjie (QXQJ), an oral solution containing various Chinese herbs, is indicated for pediatric upper respiratory tract infections. The treatment of influenza also shows potential advantages in shortening the duration of illness and improving symptoms. However, there is still a lack of high-quality clinical evidence to support this. The trial was to explore the efficacy and safety of QXQJ for treating pediatric influenza and provide an evidence-based basis for expanding its applicability. METHODS: A randomized, double-blind, double-dummy, positive-controlled, multicenter clinical trial was conducted in 14 hospitals in China. Children aged 1–13 years with influenza and “exterior and interior heat syndromes” as defined by traditional Chinese medicine (TCM) were randomly assigned to two groups with 1:1 radio. Children in the test group received QXQJ oral solution and oseltamivir simulant, while the control group received oseltamivir phosphate granules and QXQJ simulant. The duration of treatment was five days, followed by a two-day follow-up period. The primary endpoint was the clinical recovery time. Secondary endpoints included the time to defervescence, incidences of complications and severe or critical influenza, negative conversion rate, improvement of TCM syndromes, and safety profiles of the therapeutics, which mainly contained the adverse clinical events and adverse drug reactions. RESULTS: A total of 231 children were randomized to either the QXQJ (n=117) or oseltamivir (n=114) group. The FAS and PPS results showed that both groups experienced a median clinical recovery time of three days (P>0.05). The median time to defervescence of both groups were 36 hours in FAS and PPS (P>0.05), and two groups did not differ in terms of the other secondary endpoints (P>0.05). 14 patients (12.39%) in the QXQJ group and 14 patients (12.50%) in the oseltamivir group reported at least one adverse event, respectively. One serious adverse event occurred in the QXQJ group. There was no significant difference in the incidence of adverse events or adverse drug reactions between the groups. CONCLUSIONS: The efficacy of QXQJ oral solution was comparable to that of oseltamivir for treating influenza in children, with an acceptable safety profile. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900021060.

BackgroundHigh levels of circulating estradiol (E2) are associated with increased risk of breast cancer, whereas its relationship with breast cancer prognosis is still unclear. We studied the effect of E2 concentration on breast cancer survival among pre- menopausal and post- menopausal patients in China.MethodsWe evaluated this association among 8766 breast cancer cases diagnosed between 2005 and 2017 from the Tianjin Breast Cancer Cases Cohort. Levels of serum E2 were measured in pre-menopausal and post-menopausal women. Multivariable-adjusted Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) between quartile of E2 levels and overall survival (OS) and progression-free survival (PFS) of breast cancer. The penalized spline was then used to test for non-linear relationships between E2 (continuous variable) and survival endpoints.ResultsA total of 612 deaths and 982 progressions occurred over follow-up through 2017. Compared to women in the quartile 3, the highest quartile of E2 was associated with reduced risk of both PFS in pre-menopausal women (HR=1.79, 95% CI: 1.17-2.75, P=0.008) and OS in post-menopausal women (HR=1.35, 95% CI: 1.04-1.74, P=0.023). OS and PFS in pre-menopausal women exhibited a nonlinear relation (“L-shaped” and “U-shaped”, respectively) with E2 levels. However, there was a linear relationship in post-menopausal women, among whom increasing E2 was associated with escalating risks of death and progression. Moreover, patients with estrogen receptor-negative (ER-negative) breast cancer showed a “U-shaped” relationship with OS and PFS in pre-menopausal women.ConclusionsPre-menopausal breast cancer patients have a plateau stage of prognosis at the intermediate concentrations of E2, whereas post-menopausal patients have no apparent threshold, and ER status may have an impact on this relationship.

Optical multiplexing1–11 by creating orthogonal data channels has offered an unparalleled approach for information encoding with substantially improved density and security. Despite the fact that the orbital angular momentum (OAM) of light involves physical orthogonal division, the lack of explicit OAM sensitivity at the nanoscale prevents this feature from realizing nanophotonic information encoding. Here we demonstrate the viability of nanoscale information multiplexing utilizing the OAM of light. This is achieved by discovering OAM-dependent polarization ellipses in non-paraxial focusing conditions and hence synthetic helical dichroism resulting from the distinct absorption of achiral nanoparticles to the different order of OAM beams. Leveraging this mechanism, the application of subwavelength-scale focused OAM beams to self-assemble plasmonic nanoaggregates further enables six-dimensional optical information multiplexing, in conjunction with wavelength, polarization and three spatial dimensions. Our results suggest the possibility of multiplexing OAM division as an unbounded degree of freedom for nanophotonic information encoding, security imprinting and beyond. Multiplexing orbital angular momentum states as independent and orthogonal information carriers for data encryption is realized through disorder-induced synthetic helical dichroism in disordered nanoaggregates.

To make more efficient use of limited space, improve the energy dissipation effect of the step dissipator, and mitigate the effect of cavitation, we propose a segmented pier-type step dissipator structure and used a numerical simulation to study the hydraulic effects of two different arrangements of piers: a double-row arrangement and a staggered arrangement. We’ve drawn the following conclusions from our study: the segmented pier-type structure produces a large water jump at the location of the energy dissipation pier. This involves a large amount of air, promotes air-doping of the water flow in the whole section, and reduces the length of the non-air-doping zone. The staggered pier arrangement produces a better air-doping effect at the water jump and a higher air-doping concentration along the water course. The staggered arrangement also produces a better cavitation mitigation effect and is better able to stabilise the water flow; the flow velocity at the outlet is lower, so the energy dissipation effect is better. A larger positive pressure area forms at the headwater and upstream areas of the energy dissipation pier; a larger negative pressure forms at the top and backwater of the energy areas. The staggered arrangement produces a larger negative pressure; however, under various flow conditions, the difference in the energy dissipation rate between the two forms of pier arrangements is not significant. We obtained a peak energy dissipation rate of 90.04%, which represents an improved energy dissipation effect compared with the control. The step energy dissipator described here is conducive to stabilising the outlet flow, reducing cavitation damage, and improving energy dissipation. These findings provide a valuable reference for the future design of sectional pier-type step energy dissipator structures.

Stimulated-emission depletion (STED) microscopy has profoundly extended our horizons to the subcellular level1–3. However, it remains challenging to perform hours-long, autofluorescence-free super-resolution imaging in near-infrared (NIR) optical windows under facile continuous-wave laser depletion at low power4,5. Here we report downshifting lanthanide nanoparticles that enable background-suppressed STED imaging in all-NIR spectral bands (λexcitation = 808 nm, λdepletion = 1,064 nm and λemission = 850–900 nm), with a lateral resolution of below 20 nm and zero photobleaching. With a quasi-four-level configuration and long-lived (τ > 100 μs) metastable states, these nanoparticles support near-unity (98.8%) luminescence suppression under 19 kW cm−2 saturation intensity. The all-NIR regime enables high-contrast deep-tissue (~50 μm) imaging with approximately 70 nm spatial resolution. These lanthanide nanoprobes promise to expand the application realm of STED microscopy and pave the way towards high-resolution time-lapse investigations of cellular processes at superior spatial and temporal dimensions. The application of stimulated-emission depletion (STED) microscopy for deep-tissue imaging in the near-infrared optical window is challenged by high cellular autofluorescence. Here the authors present a lanthanide nanoprobe whose electronic configuration enables long-term STED imaging with reduced background noise.

Grid pattern was textured on Ti-6Al-4V alloy (TC4) substrate surface by nanosecond laser system. Laser joining of carbon fiber reinforced thermoplastic composite (CFRTP) to TC4 joints were performed, and the effect of texture grid depth was investigated. The contact angle of molten CFRTP on textured TC4 surface was measured and the tensile-shear force was tested. The fracture surface and interface morphology were observed. The results indicated that the wettability of molten CFRTP on TC4 surface improved remarkably after laser textured TC4. Shear force of CFRTP/TC4 joints was increased by 156% after laser textured TC4 surface. When the depth of grid was deeper than 100 μm, contact angle increased and incomplete filling of molten CFRTP in grid occurred, the shear force thus decreased gradually. Resin-carbon fibers mixture was adhered on the fracture surface of TC4, and the variation tendency of adhesion ratio was consistent with that of shear force. TC4 matrix was exfoliated from substrate and adhered at the fracture surface of CFRTP, indicating stronger mechanical interlocking occurred at the joining interface after laser textured TC4 surface. Beside mechanical interlocking, compound layer consisted of CTi0.42V1.58 carburization phase was also confirmed at interface, suggesting that chemical bonding also occurred at the joining interface.

Laser textured TC4 (Ti6Al4V) was connected with CFRP (carbon fiber reinforced plastic) by hot-pressing joining. Influence of textured grid width on tensile-shear force of joint was investigated, and the bonding status at the TC4/CFRP interface with and without laser texturing was compared. Experimental result indicated that laser texturing obviously improved the TC4 surface roughness and wettability of molten CFRP, which increased the interfacial joining area and thus enhanced the shear force of joint. When 0.2-mm-wide grid was adopted, surface roughness of the metal was increased by 14 times and the minimum contact angle of molten CFRP on TC4 was 49.9°. The maximum shear force was 5286 N in this case, which was about three times that of untreated case, and the adhesion ratio of resin-carbon fiber mixture also accomplished the maximum of 49.6 % of overlap area. When grid width became larger, the surface roughness and wettability decreased which caused incomplete filling of molten CFRP in textured grid and decrease of shear force. Interface and cohesive hybrid failure mode was observed from fracture surface. However, the part of oxide layer exfoliated from substrate occurred under the case of laser textured TC4 sheets, which was responsible for the enhancement of mechanical interlocking. Moreover, new chemical bonds between Ti and C were also discovered, justifying a further enhancement of tensile-shear forces.

Fiber laser joining of 6061 aluminium alloy and carbon fiber reinforced thermoplastic composite (CFRTP) was performed in this work. The effect of three process parameters including laser power, traveling speed and defocus distance on the bonding interface and joint properties was investigated. Shear tests were performed to evaluate the joint strength in different variables. X-ray photoelectron spectroscopy (XPS) was adopted to confirm the chemical states of elements at the interface. The results indicated that the shear strength of joints first increased and then decreased with the increase of heat input. Insufficient flow of CFRTP could not fill the grooves of aluminium alloy surface at low heat input. The resin was decomposed at excessisvely high heat input, causing pores remained at the interface. The fracture mode was determined as the interface failure. XPS result revealed that no new chemical bond was found at the interface, and the mechanical interlocking between aluminium alloy and CFRTP was main bonding mechanism. The maximum shear strength was 23.8 MPa, which was obtained as laser power, traveling speed and defocus distance was 1100 W, 5 mm/s and +10 mm, respectively.

Iodination of rectal hydrogel spacer increases the computed tomography (CT) visibility. The effect of iodinated hydrogel spacer material on the accuracy of proton dosimetry has not been fully studied yet. We presented a systematic study to determine the effect of iodination on proton dosimetry accuracy during proton therapy (PT).PT plans were designed for 20 prostate cancer patients with rectal hydrogel spacer. Three variations of hydrogel density were considered. First, as the ground truth, the true elemental composition of hydrogel true material (TM), verified by our measurement of spacer stopping power ratio, was used for plan optimization and Monte Carlo dose calculation. The dose distribution was recalculated with (1) no material (NM) override based on the CT intensity of the iodinated spacer, and (2) the water material (WM) override, where spacer material was replaced by water. The plans were compared with the ground truth using the metrics of gamma index (GI) and dosimetric indices.The iodination of hydrogel spacer affected the proton dose distribution with the NM scenario showing the most deviation from the ground truth. The iodination of spacer resulted in a notable increase in CT intensity and led to the treatment planning systems mistreating the iodinated spacer as a high-density material. Among the structures adjacent to the target, neurovascular bundles showed the largest dose difference, up to 350 cGy or about 5% of the prescribed dose with NM. Compared to the WM scenario, dose distribution similarity and GI passing ratios were lower in the NM scenario.The inaccurate CT intensity-based material for iodinated spacer resulted in errors in PT dose calculation. We found that the error was negligible if the iodinated spacer was replaced with water. Water density can be used as a clinically accessible and convenient alternative material override to true spacer material.

Achieving strong joining of aluminum alloy to carbon fiber thermoplastic composites (CFRTP) using laser heating was an essential method to reduce the weight of structure and save energy. In current study, a silane coupling agent was adopted on the aluminum alloy surface to improve the bonding strength of the laser joining of aluminum alloy to CFRTP. Substrate characteristics of the aluminum alloy after treatment including surface morphology, surface roughness and wettability as well as chemical composition were then studied. For comparison, identical experiments were also performed for the polished and sanded aluminum alloy. Compared to the aluminum alloy polished, the surface roughness of aluminum alloy sanded and silane treated was increased, whereas the wettability was both decreased. The rougher surface led to a worse wettability of aluminum alloy surface for these two specimens. In addition, the detected organo-functional group for the latter was also responsible for the increase of water contact angle on the aluminum alloy surface. Compared to the polished specimens, the tensile shear force of joints for sanded and silane-treated substrates averaged 1106.9N and 2959.4N respectively, which represents a respective increase of 1.2 times and 3.3 times than the polished state. Correspondingly, the tensile shear strength of joints was 6.3MPa and 16.8MPa, which was increased by 1.1 times and 2.9 times, respectively. The improved mechanical interlocking induced by increasing the surface roughness in both sanded and silane treated cases was considered to strengthen the bonding strength at the interface. Moreover, for the joints fabricated by aluminum alloy silane treated and CFRTP, the remarkable enhancement of joint strength was also related to the formation of silane coupling film on the aluminum alloy surface. The tensile shear properties of joints were also found to have a positive influence in increasing the adhesion amount of CFRTP on the fractured surface of aluminum alloy. Finally, the silane treatment was expected to play a significant role in joining aluminum alloy to CFRTP.

Single nucleotide polymorphisms (SNPs) within microRNA binding sites can affect the binding of microRNA to mRNA and regulate gene expression, thereby contributing to cancer prognosis. Here we performed a two-stage study of 2647 breast cancer patients to explore the association between SNPs within microRNA binding sites and breast cancer prognosis. In stage I, we genotyped 192 SNPs within microRNA binding sites using the Illumina Goldengate platform. In stage II, we validated SNPs associated with breast cancer prognosis in another dataset using the TaqMan platform. We identified 8 SNPs significantly associated with breast cancer prognosis in stage I (P

Superphosphate fertilizer (SSP) as an additive can reduce the nitrogen loss and increase available phosphorus in composting but few studies investigated the effect of SSP addition on heavy metal and microbial communities. In this study, different ratios (10%, 18%, 26%) of SSP were added into pig manure composting to assess the changes of heavy metal (Cu, Mn, As, Zn, and Fe) fractions, bacterial and fungal communities as well as their interactions. SSP addition at 18% had lower ecological risk but still increased the bioavailability of Cu, Mn, and Fe in composts compared to control. Adding 18% SSP into compost decreased bacterial number and increased the fungal diversity compared to CK. Redundancy analysis indicated heavy metal fractions correlated significantly with bacterial and fungal community compositions in composting with 18% SSP. Network analysis showed adding 18% SSP increased microbial interaction and positive cooperation especially enhanced the proportion of Proteobacteria and Ascomycota.

This paper applies a difference-in-differences approach to examine the effectiveness of China’s One-Vote Veto environmental regulation regime, which links pollution reduction targets with local officials’ promotion. Using a rich set of data for 286 Chinese cities, we show that the new political incentive induced significant tradeoff between economic growth and environmental protection. The regime shifts significantly reduced industrial SO2 emissions; however, the environmental improvement was limited only to the reduction of the targeted pollutants that are linked to performance evaluation. Firm-level evidence shows that emission reduction was mainly achieved by reducing new polluting production activities, increasing pollution abatement capacity and improving abatement performance. It is also found that compliance with emissions reduction targets indeed increases the promotion chances of local officials.

We investigate the two-photon fluorescence (TPF) of conjugated polymer (CP) microspheres with diameters up to tens of micrometers. Two polymers, emitting in either the violet or red, were first synthesized and characterized in terms of their one-photon fluorescence and three-dimensional internal microstructure. Under femtosecond infrared excitation, both types of microspheres showed a strong TPF, which was investigated by the excitation intensity dependence, emission spectroscopy, time-resolved luminescence, and photobleaching dynamics. While the violet-fluorescent microspheres performed similarly compared to dye-doped polystyrene counterparts emitting at a similar wavelength, the red-fluorescent microspheres showed a two-orders-of-magnitude stronger TPF. This excellent performance is attributed to enhanced hyperpolarizability associated with intermolecular interactions in the polymer solid, indicating a route toward designed CP microspheres that could outperform currently-available microparticles for sensing or imaging applications involving two-photon fluorescence.