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Extreme hypoxia inside solid tumors is the primary barrier against the advance of chemotherapy and photodynamic therapy (PDT). To address this problem, a hybrid nano-enzyme prodrug system was developed to alleviate hypoxia as well as simultaneously sensitize chemo-photodynamic therapy. Lactobionic acid (LA) and doxorubicin (DOX) precursor (cis-aconitic anhydride-linked doxorubicin, CAD) were pre-conjugated onto the side chain of catalase (CAT), then co-assembled with chlorin e6 (Ce6) to form LA-CAT-CAD@Ce6 nanoparticles (LCC@Ce6-NPs). LA as the active-targeting ligand increased cellular internalization, CAD as the pH-sensitive component triggered rapid drug release, Ce6 as the photosensitizer induced reactive oxygen species (ROS) generation, and CAT decomposed intracellular H 2 O 2 to produce oxygen in situ. Oxygen production efficiently decreased the expression of hypoxia-inducible factor-1α (HIF-1α) and P-glycoprotein (P-gp), which enhanced chemotherapy efficiency. In addition, sufficient oxygen further amplified PDT-mediated cell-killing and apoptosis in hypoxic tumor. In vivo studies showed that combined chemo-photodynamic therapy by LCC@Ce6-NPs led to the most effective inhibition of tumor growth (TGI>90%), and even partially ablated tumor. Thus, this nano-enzyme prodrug platform can be a potentially effective treatment in clinical cancer therapy, and married to other therapeutic agents. Hypoxia in solid tumors seriously impedes the efficacy of chemotherapy or photodynamic therapy. Herein, we designed hybrid nano-enzyme prodrug particles to improve hypoxia-mediated limitations on cancer therapy. Lactobionic acid (LA) as the hydrophilic outer layer of particles increased cellular uptake by receptor-mediated endocytosis, and cis-aconitic anhydride-linked doxorubicin (CAD) as the pH sensitive component inside particles efficiently triggered DOX and Ce6 release. More importantly, catalase (CAT) as the backbone of particles was capable of greatly relieving tumor hypoxia through catalyzing the decomposition of H2O2 in situ. Oxygen re-generation not only prevented hypoxia-mediated chemo-resistance, but also amplified PDT-induced ROS cell-killing ability. As a result, the multiple combination action of this nano-system could simultaneously sensitize chemo-photodynamic therapy, thus significantly enhancing tumor therapy. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• According to COMSOL calculations, the absorption film has four perfect absorption peaks in the terahertz narrowband and exhibits polarization incoherence, which means that the absorption film has good performance. • By changing the physical parameters, the active tunability of the film in a wide range is achieved. • The absorption film has high refractive index sensitivity, which means it has extremely high application prospects. • With simple structures and materials, the phenomenon of absorption bandwidth of the absorber also facilitates the study of conversion and regulation between narrowband and broadband. Here, a simple four-band terahertz tunable narrowband absorber is proposed, which can achieve multimodal perfect absorption within 1–9 THz. We analyzed the physical mechanisms behind local surface plasmon resonance and impedance matching based on theoretical principles. By controlling the structural parameters, we use the eigen-mode and external field excitation to obtain the absorption peak and electromagnetic field distribution of the narrowband sensor under different structural parameters. Additionally, we studied the effect of the angle of incidence electromagnetic waves on the function of the absorber, found that the absorber has excellent characteristics in both low and high frequency states. We carry out a substance detection on four perfect absorption modes. The ambient refractive index sensitivity is 881.35 GHz / RIU , 439.65 GHz / RIU , 2664.46 GHz / RIU , 4501.19 GHz / RIU. The four-peak narrowband high-performance absorber designed by us has a huge development prospect in most important areas such as resource detection and biomedical diagnosis. [Display omitted] [ABSTRACT FROM AUTHOR]

Tumor extracellular matrix (ECM) still remains a major barrier that hinders the diffusion of drug in tumor parenchyma. We design a lactobionic acid (LA) and bromelain dual-functional nanoparticles as doxorubicin carriers. LA can increase the nanoparticles' tumor-targeting ability, while bromelain can enhance the permeation of nanoparticles in tumor parenchyma due to the hydrolytic activity to ECM. The chemical structures of these modified macromolecules were characterized by 1 H NMR, FT-IR and UV spectrum. Drug-loaded nanoparticles as final drug formulations were observed in terms of size, zeta potential and micromorphology. Monolayer cells and three-dimensional cell spheroids were used to investigate the influence of LA and bromelain on the nanoparticles' cellular uptake, cytotoxicity, accumulation and penetration. In vivo drug distribution and antitumor activity results demonstrated that bromelain increased nanoparticles penetration and diffusion ability in tumor area upon the digestion of ECM, leading to higher drug concentration in tumor area and superior antitumor effect. [ABSTRACT FROM AUTHOR]

Purpose: This study sought to investigate the characteristics of morphology, compositions and distribution of carotid atherosclerotic plaques in asymptomatic elderly population using three dimensional (3D) multicontrast magnetic resonance vessel wall imaging.Materials and Methods: 146 asymptomatic elderly subjects (≥60years) were recruited and underwent 3D multicontrast MR vessel wall imaging for bilateral carotid arteries on a 3.0T MR scanner. The presence of carotid atherosclerotic plaque was determined and the stenosis was measured. The characteristics of plaque morphology and compositions were evaluated and compared among distal internal carotid artery (D-ICA), proximal-ICA (P-ICA), carotid bulb (CB), distal common carotid artery (D-CCA) and proximal-CCA (P-CCA).Results: Of all recruited 140 subjects (72.1±5.7years, 63 males), 87 (62.1%) had carotid plaques, 17 (12.1%) had high-risk plaques and 51 (36.4%) had multiple plaques. Of all 280 carotid arteries, only 16 (5.7%) had luminal stenosis (21.1%±11.4%). Among carotid arteries without luminal stenosis, the prevalence of plaque and high-risk plaques was 43.2% and 8.3%, respectively. Carotid plaques were mostly found in CB segment (33.9%), followed by P-ICA (13.6%), P-CCA (11.1%), D-CCA (4.6%) and D-ICA (3.6%). Age was independently associated with presence of multiple carotid plaques (odds ratio, 1.835; 95% confidence interval, 1.196-2.815; P=0.005).Conclusion: Carotid artery atherosclerotic plaques are prevalent and a substantial number of high-risk plaques can be found in the asymptomatic elderly subjects. Longitudinal studies are warranted to investigate the risk of having ischemic stroke for asymptomatic elderly individuals with carotid artery high risk plaques. [ABSTRACT FROM AUTHOR]

The intrinsic viscosity and rheological properties of guar gum (GG), hydroxypropyl guar (HPG) and carboxymethyl guar (CMG) in seawater and the effects of shear rate, concentration, temperature and pH on these properties were investigated. An intrinsic viscosity-increasing effect was observed with GG and HPG in seawater (SW) compared to deionized water (DW), whereas the intrinsic viscosity of CMG in seawater was much lower than that in DW due to a screening effect that reduced the repulsion between the polymer chains. Regardless of the functional groups, all sample solutions was well characterized by a modified Cross model that exhibited the transition from Newtonian to pseudoplastic in the low shear rate range at the concentrations of interest to industries, and their viscosity increased with the increase in their concentration but decreased with the increase in temperature. In contrast to nonionic GG or HPG, anionic CMG had a slightly decreased viscosity property in SW, exhibiting polyelectrolyte viscosity behavior. The α value in the zero-shear rate viscosity vs. concentration power–law equation for the samples gave the order of CMG > HPG > GG while the SW solution of CMG had the lowest viscous flow activation energy and exhibited a strong pH-dependent viscosity by a different shear rate. [ABSTRACT FROM AUTHOR]

We present here our recent studies on the magnetic-field-guided assembly of colloidal matter. Starting from a brief introduction of the magnetic interactions exerted on colloidal nanostructures, we discuss how magnetic fields drive their assembly into one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) ordered structures. This principle is further demonstrated in the assembly of colloidal matter on macroscopic and microscopic magnetized patterns with defined field strengths and spatial distributions. [ABSTRACT FROM AUTHOR]

Abstract: Topography of a granite surface has an effect on the vertical positioning of a wafer stage in a lithographic tool, when the wafer stage moves on the granite. The inaccurate measurement of the topography results in a bad leveling and focusing performance. In this paper, an in situ method to measure the topography of a granite surface with high accuracy is present. In this method, a high-order polynomial is set up to express the topography of the granite surface. Two double-frequency laser interferometers are used to measure the tilts of the wafer stage in the X- and Y-directions. From the sampling tilts information, the coefficients of the high-order polynomial can be obtained by a special algorithm. Experiment results shows that the measurement reproducibility of the method is better than 10nm. [Copyright &y& Elsevier]

Amorphous SiO2 (a-SiO2) films were prepared by reactive RF magnetron sputtering method in an oxygen and argon mixture at room temperature. The chemical structure and electrical properties of the films were investigated as a function of the gas volume ratio [O2]/[Ar]. When Ar was fixed at 40 sccm and O2 was increased, deposition rate would decrease firstly, then increase and finally decrease. When the [O2]/[Ar] ratio was larger than 0.075, oxide films having a stoichiometric composition can be obtained. With increasing [O2]/[Ar], the resistivity and breakdown strength of electric field for the films increased, while buffered HF etch rate decreased. Neither absorption bands due to H–OH bonds in Fourier-transform spectra, nor porosity detected by electronic scan microscope was found in all films. It was suggested that the films were densified and had good dielectric properties. [Copyright &y& Elsevier]

In this paper, we propose and demonstrate a hybrid bismuth-doped fiber approach for broadband amplification in the O + E bands. The bismuth-doped fibers were fabricated by the MCVD process combined with solution doping technique. The amplification performance was investigated by the two pump wavelengths of 1240 nm and 1270 nm combined with different pump configurations. The results show that the maximum gain of 38.2 dB with the NF of 3.7 dB was achieved at 1350 nm by the bi-directional pumping configuration. Furthermore, the hybrid bismuth-doped fiber was demonstrated to improve the gain in E-band and maintain the gain flatness between O-band and E-band. A wide bandwidth of ∼150 nm (1310 nm–1460 nm) was achieved by the hybrid fiber, with a gain >15 dB, gain flatness of 8 dB, and NF of 4.1 dB–5.7 dB. [ABSTRACT FROM AUTHOR]

Patients with rectal cancer with a permanent colostomy often have issues in physical, psychological and social domains. Since discharge is an important transition period, the patient experience at that time is worthy of attention. The aim of this study was to explore the immediate postoperative experiences before discharge among patients with rectal cancer and a permanent colostomy in China. A qualitative design was used. Semi-structured interviews were conducted with 18 patients newly living with colostomy in China, who were asked open-ended questions about their postoperative experience. The thematic analysis approach was used to analyze the data. Four themes and twelve sub-themes were identified from the interviews: (1) psychological reactions (stoma self-acceptance, negative emotion and social isolation), (2) daily life concern (daily life misunderstandings, sexual life compromise and work restriction), (3) stoma care consideration (strong stoma self-care willingness, decreased stoma self-care confidence and access to high-quality stoma care), and (4) support from others (enterostomal nurses, family members and stoma friends). Colostomy patients experience various obstacles in physiological, psychological, and societal aspect. Nurses should provide effective discharge guidance to correct misunderstandings about the stoma, refer patients to psychological care, and promote transitional care. • Patients with rectal cancer and a permanent colostomy often experience a series of complex emotions and challenges before discharge. • These immediate postoperative experience re especially prominent and may impact the adaptation process after discharge. • The experiences among them were psychological reactions, daily life concern, stoma care consideration and support from other. [ABSTRACT FROM AUTHOR]

Acrylamide (AA) can have deleterious effects on freshwater fish. However, its adverse effects on euryhaline fish are still unknown. In this study, embryos of Oryzias melastigma were exposed to different concentrations of AA to investigate its effect on early developmental disorders. After 21 days of exposure, AA significantly inhibited the hatching rate and delayed the hatching time of embryos, and led to developmental delay, teratogenesis, and locomotion impairments in larvae. RNA-sequencing data of larvae indicated that AA upregulated the expression of hemoglobin and myoglobin involved in oxygen transport and angiopoietin 1, integrin, and matrix metallopeptidases related to angiogenesis and downregulated the expression of early growth response genes and synaptotagmin-2 related to neural plasticity and neurotransmitter release. Overall, our study showed that AA caused deleterious effects on the early development of euryhaline fish through hypoxic stress and neurotoxicity, providing a scientific basis for the environmental risk assessment of marine AA. • AA reduces hatchability and delays hatching time in marine medaka embryos. • AA leads to teratogenesis and locomotion impairments in larvae of marine medaka. • RNA-seq indicates that AA induces hypoxia stress and neurotoxicity. • AA exhibits the early developmental toxicity on marine fish. [ABSTRACT FROM AUTHOR]

Cisplatin resistance is a daunting obstacle in cancer therapy and one of the major causes for treatment failure due to the inadequate drug activity and apoptosis induction. To overcome cisplatin resistance, we proposed a multifunctional nanogel (designated as Valproate-D-Nanogel) capable of reactivating cisplatin and enhancing early apoptosis. This Valproate-D-Nanogel was prepared through copolymerizing carboxymethyl chitosan with diallyl disulfide and subsequent grafting with valproate to reverse the drug-resistance in cisplatin-resistant human lung adenocarcinoma cancer. It can significantly increase the proportion of G2/M phase (up to 3.2-fold enhancement) to reactivate cisplatin via high level of G2/M arrest induced by valproate. Meanwhile, the intracellular ROS-P53 crosstalk can be upregulated by diallyl disulfide (up to 8-fold increase of ROS) and valproate (up to 18-fold increase of P53) to enhance early apoptosis. The synchronization of enhanced G2/M arrest and ROS-P53 crosstalk devotes to reverse the cisplatin resistance with a high level of resistance reversion index (50.22). As a result, improved in vivo tumor inhibition (up to 15-fold higher compared to free cisplatin) and decreased systemic toxicity was observed after treatment with Valproate-D-Nanogels. Overall, this nanogel can effectively inhibit cisplatin-resistance cancer through combined pathways and provides an effective approach for overcoming cisplatin-resistance in cancer treatment. Image 1 [ABSTRACT FROM AUTHOR]

Downward flame spread over polymer materials is one of the typical hazardous scenarios in building fires, and also an important feature for fire safety research. This work was motivated to study the coupling effects of ambient pressure and orientation on downward fire propagation with a widely used thermal insulation polymer, flexible polyurethane (FPU). Comparative experiments were conducted under 3 different pressures (75 kPa, 80 kPa and 100 kPa) and 4 angles of inclination (0°, 30°, 60°, 90°) respectively, to investigate the variation of fire characteristics including flame tilt, length, spread velocity, burning rate, and related heat transfer mechanisms. The results showed non-monotonic tendencies of these parameters with enlarged inclination angle, and more complicated relationships by coupling pressure effect. Flame tilt was found be determined by the asymmetric entrainment induced, and also a key factor controlling heat preheating mechanism. Variation of spread velocity and consequent burning rate and flame length were discussed theoretically based on different preheating heat fluxes including convection, radiation and conduction from fire and solid phase. Particularly, a semi-quantitative correlation for coupling effects of pressure and inclination on flame spread velocity was proposed, which could help to improve the understanding of fire evaluation under low pressures. • Pressure effects on downward flame propagation at multiple orientations were studied. • Tendency of flame tilt angle with enlarged fuel inclination angle was analyzed. • Correlations of pressure/inclination with flame length and burning rate were given. • Coupling effects on downward flame spread velocity was proposed theoretically. [ABSTRACT FROM AUTHOR]

Inflammatory myofibroblastic tumor (IMT) is a rare tumor with an indolent course. It is less often reported as a second tumor that occurs after treatment of malignant tumors in pediatric patients. Here, we report a case of IMT following Wilms tumor (WT), and conduct a literature review concerning IMTs and WT to evaluate the diagnostic possibility of IMT as a second tumor. The coexistence of the 2 tumors may cause confusion as to whether they share genetic links or that IMTs may appear as late effects of the treatment of WT. [ABSTRACT FROM AUTHOR]

• Thee type of BICs can exist in bulk Dirac semimetal metasurface. • The quasi-BIC mode has high refractive index sensing sensitivity and figure-of-merit. • The sensing sensitivity and FOM of quasi-BIC can be enhanced by adjusting the Ef. Bound states in the continuum (BICs) are located states embedded in the continuous spectrum, therefore, they have infinite quality (Q) factor. Here, we find that many types of BICs including symmetry-protected BIC, accidental BIC and Friedrich-Wintgen BIC can exist in bulk Dirac semimetal (BDS) metasurface. We studied the refractive index sensing performance of the quasi-BIC mode that is close to BIC mode, and found that the quasi-BIC has high refractive index sensing sensitivity and figure-of-merit (FOM) when the external refractive index changes. The effect of Fermi energy of the BDS metasurface on quasi-BIC mode is researched. The FOM of the quasi-BIC increases from 202 to 663 when the Fermi energy is adjusted from 0.2 eV to 1 eV, and the sensing sensitivity maintains at about 158 GHz/RIU. The origin of the improved sensor performance is that the Q factor of quasi-BIC mode can be enhanced by controlling the Fermi energy of BDS, which may expand the applications range of this new class of plasmonic materials. [ABSTRACT FROM AUTHOR]

• We proposed a low differential modal gain (DMG) l -band 5-LP modes fiber amplifier by using an extremely simple fiber design. • For the first time to the best of our knowledge, the optimization effects of the fiber structural parameters on the performance of the DMG and gain was investigated in the ordinary FM-EDF. • We fabricated a FM-EDF, for which the NA was improved by increasing the Al3 + -doped concentration and the core radius was properly designed to 8.1 um, aiming to realize a powerful trade-off between the DMG and gain. • For the 5-LP modes, the gain can reach to 19 dB and the DMG can be reduce to < 1.8 dB in the l -band. We numerically and experimentally demonstrated a low different modal gain (DMG) 5-LP modes l -band fiber amplifier by using an extremely simple fiber structure. The effect of fiber structure parameters on gain and DMG optimization in the uniform doping few-mode erbium-doped fiber (FM-EDF) was investigated to archive a powerful trade-off between DMG and gain performance. A FM-EDF was fabricated by modified chemical vapor deposition (MCVD), for which the NA was improved to 0.25 by increasing the doping concentration of Al3+ and the core radius was properly selected to 8.1 μm. In the case of core pumping of the LP 11 mode at 1480 nm, a maximum DMG of < 1.8 dB and a maximum gain of 19 dB was obtained for all five modes across the l -band (1570–1605 nm). The results suggested that our proposed erbium-doped fiber amplifier has great potential for large-capacity long-haul few-mode mode division multiplexing (MDM) transmission system. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the characteristics of plaque in the thoracic aorta using three dimensional multicontrast magnetic resonance imaging.Materials and Methods: Elderly subjects (≥60years) were recruited in this study. Thoracic aorta was imaged on a 3.0T MR scanner by acquiring multicontrast sequences. The plaque burden was evaluated by measuring lumen area, wall area, wall thickness, and normalized wall index. The presence or absence of plaque and intraplaque hemorrhage (IPH)/mural thrombus (MT) were identified. The characteristics of atherosclerosis among different thoracic aorta segments (AAO: ascending aorta; AOA: aortic arch, and DOA: descending aorta) were determined.Results: Of 66 recruited subjects (mean age 72.3±6.2years, 30 males), 55 (83.3%) had plaques in the thoracic aorta. The prevalence of plaque in AAO, AOA, and DAO was 5.4%, 72.7%, and 71.2%, respectively. In addition, 21.2% of subjects were found to have lesions with IPH/MT in the thoracic aorta. The prevalence of IPH/MT in segment of AAO, AOA and DAO was 0%, 13.6%, and 12.1%, respectively. The aortic wall showed the highest NWI in DAO (34.1%±4.8%), followed by AOA (31.2%±5%), and AAO (26.8%±3.3%) (p<0.001).Conclusion: Three dimensional multicontrast MR imaging is capable of characterizing atherosclerotic plaques in the thoracic aorta. The findings of high prevalence of plaques and the presence of high risk plaques in the thoracic aorta suggest early screening for aortic vulnerable lesions in the elderly. [ABSTRACT FROM AUTHOR]