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An exploratory study of the lead-tellurium-oxygen phase space led to two new compounds, Ba3PbTe6O16 (BPTO) and Na2Pb9(μ6-O)2(Te2O10)2 (NPTO), which were synthesized under hydrothermal conditions at 550 °C and 210 °C, respectively, and characterized by single-crystal X-ray diffraction, infrared and X-ray photoelectron spectroscopy. BPTO adopts a layer structure. The Te4+ cation in BPTO is bonded to four oxygen atoms at about 2.0 A with two more oxygens at about 3.0 A. The seesaw-shaped TeO4 units share corners to form 2D layers containing six-membered rings and the Ba2+ and Pb2+ cations are situated in the interlayer region. The structure of NPTO contains dimers of edge-sharing Te6+O6 octahedra, which are connected through five-coordinate Pb2+ cations. A unique six-coordinate O atom is at the center of the octahedron formed by five Pb2+ and one Na+ cations. BPTO is one of the few metal tellurites which were synthesized under supercritical hydrothermal reaction conditions. The Pb2+ cation in NPTO shows pronounced stereochemical effects of the lone electron pair. In contrast, BPTO shows no stereochemical evidence of the inert pair.

The design and synthesis of crystalline materials have been a subject of intensive research because of their interesting structures, physicochemical properties, and potential applications. However, the crystalline structure of organic-inorganic hybrid materials collapses to lose the structural features of the original networks and/or frameworks when exposed to different stimuli such as pH, vapor, water, high temperature, and organic solvents. This hampers further studies focusing on practical applications. Although several review articles provide reasonable pathways for the preparation of stable metal-organic frameworks (MOFs) and coordination polymers (CPs), the synthesis and design of stable materials containing organic species remain challenging. In this frontier article, we discuss the development of crystalline MOF, CP, metallophosphate, and metallophosphite materials, and provide a feasible approach for the formation of stable organic-inorganic hybrid compounds that combine MOFs (or CPs) and phosphate (or phosphite) building elements. In addition to their interesting structures, the synthetic strategies and structural stabilities of such hybrid composites are also presented.

The first example of a thio-functionalized zincophosphite material (NTOU-2S) incorporating the 2,5-thiophenedicarboxylate (TPDC) ligands was synthesized using a hydro(solvo)thermal method and structurally characterized by single-crystal X-ray diffraction. Interestingly, the perspective view of the crystal structure for NTOU-2S is similar to our previous report of NTOU-2 but the carboxylate organic ligands (TPDC for NTOU-2S; 1,4-benzenedicarboxylate, BDC, for NTOU-2) in both compounds adopt different types of bis-monodentate coordination models (the unusual cis bonding versus a trans linkage) to bridge the metal atoms of inorganic tubes in the formation of large-channel zincophosphite frameworks, resulting in structural and functional diversities. The thiophene-based compound also displayed higher thermal stability and removal ability for the softer Hg2+ cations from water solutions than the performance of sulfur-free NTOU-2. In addition, the synthesis, structural characteristics, removal properties of heavy metal cations, and thermal and chemical stabilities for both compounds were also reported.

The nonlinear coefficient γ is central to the study of cubically nonlinear optical guided-wave structures. It is well understood for lossless waveguides, but less so for lossy systems. A number of methods for calculating γ in lossy systems have been proposed, each resulting in different expressions. Here we identify the most accurate and practical expression for γ . We do so by applying the different expressions γ to air–gold surface plasmon polariton modes in the interband region of gold and compare with a fully numerical iterative method. We thus resolve the outstanding issue of which expression for the nonlinear coefficient to use for lossy waveguides, enabling new insights into the nonlinear response of such systems.

Polymer-templated nematic liquid crystal (LC) holographic gratings via visible-light recording are presented in the presence of reactive mesogens (RMs) and rose bengal (RB)/N-phenylglycine (NPG) photoinitiation systems. By optimizing the concentration of RMs in the polymer-templated LC gratings, the template after being washed out can be refilled with suitable fluidic components. And the dependence of the first-order diffraction efficiency (DE) on the concentration of RB and NPG molecules was discussed in detail. The polarization-dependency of diffraction properties was also investigated. It is revealed that the diffractive behaviors of polymer-templated LC gratings can be dynamically reconfigured by varying temperature or refilling organic solutions with different refractive index (RI). Furthermore, the potential for recording holograms using green light is explored. We expect that the reconfigurable polymer-templated LC gratings fabricated via visible-light interference would provide a facile approach to regulate the diffraction properties of holographic gratings apart from electric field, thus paving a way towards a class of novel anti-counterfeiting devices.

We compare expressions for the nonlinear coefficient $\gamma$ of several plasmonic waveguides against numerical methods. Using gold in its interband region as the metal, we identify the most accurate expression for $\gamma$ in lossy systems. 10.1364/CLEOPR.2020.C4B_4

The nonlinear coefficient γ is a key parameter for studying nonlinear pulse propagation, as it relates the power in a waveguide mode to the nonlinear phase shift per unit length. It is well understood in dielectric waveguides, but less so in lossy plasmonic waveguides. A number of methods for calculating γ have been proposed, each producing different expressions. Here, we comprehensively compare these methods for a surface plasmon polariton propagating at a gold-air interface, obtaining new insights into the nonlinear response of lossy waveguides.

OBJECTIVE This study aimed to investigate the feasibility of blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) to evaluate visceral adipose tissue (VAT) oxygenation in Zucker diabetic fatty (ZDF) rats and its associations with systemic metaflammation. METHODS Five-week-old ZDF rats and Zucker lean (ZL) rats were fed a high-fat diet (HFD) for 18 weeks. A baseline BOLD-MRI scan of perirenal adipose tissue was performed after 8 weeks of HFD feeding, and then the rats were randomized to receive pioglitazone or a vehicle for the following 10 weeks. At sacrifice, BOLD-MRI scan, Hypoxyprobe-1 injection, and circulating T helper 17 (Th17), regulatory T (Treg) cells, and monocyte subtype flow cytometry analysis were performed. RESULTS HFD feeding led to a significant increase in VAT BOLD-MRI R2* signals (20.14 ± 0.23 per second vs. 21.53 ± 0.20 per second; P = 0.012), an indicator for decreased oxygenation. R2* signal was significantly correlated with VAT pimonidazole adduct-positive area, insulin resistance, Th17 and Treg cells, CD43 + and CD43+ + monocyte subtypes, and VAT macrophage infiltration. Pioglitazone treatment improved the insulin resistance and was associated with a delayed progression of VAT oxygenation. CONCLUSIONS This work demonstrated the feasibility of BOLD-MRI for detecting the VAT oxygenation status in ZDF rats, and the BOLD-MRI signals were associated with insulin resistance and systemic metaflammation in ZDF rats during the development of obesity.

Assessing liver fibrosis with chronic hepatitis B (CHB) in patients is quite important. Some non-invasive approaches for evaluating liver fibrosis include blood tests and ultrasound elastography. How to effectively combine multiple methods to improve the diagnostic performance remains a challenging problem. The main goal of this paper is to assess and stage liver fibrosis in CHB using feature selection and machine learning methods based on multimodal data. Popular machine learning approaches (e.g., support vector machine (SVM)) and feature selection (FS) were explored to stage the CHB. 16 volunteers and 92 patients with CHB were investigated for liver fibrosis staging based on transient elastography (TE) and acoustical radiation force impulse imaging (ARFI) data. The accuracy of the staging result using FS and a SVM classifier was an accuracy of 90.68% for significant fibrosis (≥F2) and an accuracy of 93.52% for cirrhosis (F4), respectively. The proposed method also increased the sensitivity, specificity, and area under curve (AUC) values for both significant fibrosis and cirrhosis diagnosis, which is very promising for staging liver fibrosis from multimodal information. It outperforms any single method and their linear combination and also achieves a state-of-the-art performance.

The n-channel behavior has been occasionally reported in the organic field-effect transistors (OFETs) that usually exhibit p-channel transport only. Reconfirmation and further examination of these unusual device performances should deepen the understanding on the electron transport in organic semiconductors. 6,13-bis(triisopropyl-silylethynyl) pentacene (TIPS-pentacene), a widely examined p-channel material as Au is used for source-drain electrodes, has recently been reported to exhibit electron transport when grown from non-polar solvent on divinyltetramethyldisiloxanebis (benzocyclobutene) (BCB) dielectric, spurring the study on this unusual electron transport. This paper describes FET characteristics of solution-grown TIPS-pentacene single crystals on five polymer gate dielectrics including polystyrene (PS), poly(methyl methacrylate) (PMMA), poly(4-vinyl phenol) (PVP), poly(vinyl alcohol) (PVA) and poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)). In addition to the p-channel behavior, electron transport occurs in the crystals on PMMA, PS, thick PVA (40 nm) and a bilayer dielectric of PMMA on P(VDF-TrFE-CFE), while does not on PVP and thin PVA (2 nm). The two distinct FET characteristics are consistent with the previous reported trap effect of hydroxyl groups (in PVP and PVA) and reduced injection barrier by Na+ ions (as impurity in PVA). The highest electron mobility of 0.48 cm2 V−1 s−1 has been achieved in the crystals on PMMA. Furthermore, the electron transport is greatly attenuated after the crystals are exposed to the vapor of a variety of polar solvents and the attenuated electron transport partially recovers if the crystals are heated, indicating the adverse effect of polar impurities on electron transport. By reconfirming the n-channel behavior in the OFETs based on TIPS-pentacene, this work has implications for the design of n-channel and ambipolar OFETs.

We report a magnetically transportable microlaser with cholesteric liquid crystal (CLC) core-shell structure, operating in band-edge mode. The dye doped CLC shells as a water-in-oil-in-water (W/O/W) double emulsion were fabricated by microfluidics. Water-dispersible Fe3O4 magnetic nanoparticles were incorporated in the inner aqueous phase by taking advantage of the immiscibility with the middle CLC oil phase. The influence of temperature and shell thickness on laser properties was discussed in detail. The non-invasive manipulation of microlasers was realized under a magnetic field. The dependence of velocity on the viscosity of the carrying fluid and size of the core-shell structure was theoretically analyzed and experimentally investigated using a prototype electromagnetic platform. We also discussed the design principles for this type of DDCLC core-shell structure. Such magnetically transportable microlasers offer promise in in-channel illumination applications requiring active control inside micro-channels.

Zeolitic imidazolate framework-8 (ZIF-8) nanocrystalline layers were grown on carboxylate-terminated sol–gel films patterned with surface-relief microstructures. The coverage of ZIF-8 nanocrystals was significantly affected by the surface morphology, like the size and interspace of microstructures. Its vertically aligning ability to a typical nematic liquid crystal (LC) E7 was verified and its applications as a hybrid aligned nematic (HAN) LC cell-based voltage-dependent light modulator and a switchable diffraction grating were demonstrated.

Out-of-plane lattice plasmons (OLPs) supported by metallic nanoparticle arrays are promising for diverse applications due to their remarkably narrow linewidths and significant enhancement of local fields. Here we investigate the necessary conditions for metallic nanoparticle arrays to achieve OLPs. Our results show that, besides the prerequisites of large height, oblique incidence, and TM polarization, which have been pointed out by the literature; the array period should be properly designed within a limited range, the dielectric environment should be homogeneous, and the height and the angle of incidence need to be optimized. We expect this work will advance the understanding and engineering of OLPs in metallic nanoparticle arrays and promote their applications in nanolasers, ultrasensitive biochemical sensors, and nonlinear optics., Comment: 9 pages, 8 figures

This study aimed to investigate the feasibility of blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) to evaluate visceral adipose tissue (VAT) oxygenation in Zucker diabetic fatty (ZDF) rats and its associations with systemic metaflammation.Five-week-old ZDF rats and Zucker lean (ZL) rats were fed a high-fat diet (HFD) for 18 weeks. A baseline BOLD-MRI scan of perirenal adipose tissue was performed after 8 weeks of HFD feeding, and then the rats were randomized to receive pioglitazone or a vehicle for the following 10 weeks. At sacrifice, BOLD-MRI scan, Hypoxyprobe-1 injection, and circulating T helper 17 (Th17), regulatory T (Treg) cells, and monocyte subtype flow cytometry analysis were performed.HFD feeding led to a significant increase in VAT BOLD-MRI R2* signals (20.14 ± 0.23 per second vs. 21.53 ± 0.20 per second; P = 0.012), an indicator for decreased oxygenation. R2* signal was significantly correlated with VAT pimonidazole adduct-positive area, insulin resistance, Th17 and Treg cells, CD43 + and CD43+ + monocyte subtypes, and VAT macrophage infiltration. Pioglitazone treatment improved the insulin resistance and was associated with a delayed progression of VAT oxygenation.This work demonstrated the feasibility of BOLD-MRI for detecting the VAT oxygenation status in ZDF rats, and the BOLD-MRI signals were associated with insulin resistance and systemic metaflammation in ZDF rats during the development of obesity.

To investigate the combined diagnostic accuracy of acoustic radiation force impulse (ARFI), aspartate aminotransferase to platelet ratio index (APRI) and Forns index for a non-invasive assessment of liver fibrosis in patients with chronic hepatitis B (CHB).In this prospective study, 206 patients had CHB with liver fibrosis stages F0-F4 classified by METAVIR and 40 were healthy volunteers were measured by ARFI, APRI and Forns index separately or combined as indicated.ARFI, APRI or Forns index demonstrated a significant correlation with the histological stage (all P0.001). According to the AUROC of ARFI and APRI for evaluating fibrotic stages more than F2, ARFI showed an enhanced diagnostic accuracy than APRI (P0.05). The combined measurement of ARFI and APRI exhibited better accuracy than ARFI alone when evaluating ≥ F2 fibrotic stage (Z = 2.77, P = 0.006). Combination of ARFI, APRI and Forns index did not obviously improve the diagnostic accuracy compared to the combination of ARFI and APRI (Z = 0.958, P = 0.338).ARFI + APRI showed enhanced diagnostic accuracy than ARFI or APRI alone for significant liver fibrosis and ARFI + APRI + Forns index shows the same effect with ARFI + APRI.

In this study, an environmental-friendly hydrothermal pretreatment of Eucalyptus fiber followed with alkali post-treatment was developed to produce bioethanol efficiently. This biorefinery process allowed all major components of biomass being converted into high value-added products. The chemical and structural features of the residual hemicelluloses isolated with alkali from the hydrothermal pretreated Eucalyptus fiber, were comparatively investigated. Sugar and spectral analyses indicated that the hemicelluloses were mainly composed of glucuronoxylans, and especially hemicelluloses prepared at higher temperature (180 °C) contained higher contents of glucomannans and α-glucan. Hydrothermal pretreatment resulted in a significant hydrolysis of the glycosidic linkages in xylan backbone, and thus the molecular weight of the hemicelluloses was significantly reduced from 56,520 to 7780 g/mol with the increase of temperature. This suggested that a combination of hydrothermal pretreatment at low temperatures (100–140 °C) and alkali post-treatment was an effective technique for isolating of hemicelluloses from Eucalyptus fiber.

Background & Aims Accurate assessment of liver fibrosis in patients with chronic hepatitis B (CHB) is necessary not only to predict the long-term clinical course but also to determine an appropriate antiviral therapy scheme. Several noninvasive approaches – serum markers and elastography – have been proposed as alternatives for the histopathological analysis of liver biopsies. The aim of this study was to evaluate two ultrasound elastography methods (ARFI and TE) and one biochemical test (APRI), as well as their optimal linear combination, in the assessment of liver fibrosis in CHB. Methods Ninety five patients with CHB and 16 volunteers underwent ARFI, TE and APRI; and liver fibrosis was staged in the patients by a liver biopsy. An optimal linear combination of the three methods was developed, and its diagnostic performance was evaluated by a 10-fold cross-validation. Results The accuracy of the linear combination was 83.86% and 91.88% for significant fibrosis (≥F2) and cirrhosis (F4), respectively, higher than those obtained for ARFI (83.50%, 88.76%), TE (75.27%, 87.61%) and APRI (73.29% and 81.67%). The combination also increased the sensitivity and the negative predictive values for the diagnosis of significant fibrosis and cirrhosis. Conclusions The optimal linear combination algorithm is effective for noninvasive staging of liver fibrosis in CHB. However, linear combination has its own limitations; nonlinear methods may eventually reveal even clearer diagnostic results.

To investigate the value of acoustic radiation force impulse (ARFI) in evaluating the stage of hepatic fibrosis and early stage cirrhosis.Sixty-six patients with viral hepatitis underwent liver biopsy and 33 normal subjects (S0) were selected to accept ARFI,the shear wave velocity of hepatic segments s5, s6, s7, s8 and size of liver were measured. The results of liver and spleen size and portal vein's diameter were also measured.The 66 patients were divided into 3 groups: S1, S2-S3, S4. ARFI for 66 patients and 33 normal subjects showed good image quality. There were statistically significant differences between S4 group and S0 group, S1 group, S2-S3 group for the shear wave velocity of hepatic segments s5, s6, s7, s8 (P0.05). Between S2-S3 group and SO group S1 group, the shear wave velocity of hepatic segments s5, s6, s7, s8 also have statistically significant differences (P0.05), other parameters showed no significant difference (P0.05). Spleen size and the portal vein's diameter of S4 group were larger than those in other groups (P0.05).The invasive acoustic radiation force impulse could evaluate the stage of hepatic fibrosis and early stage cirrhosis in patients suffering from viral hepatitis. The measurement was feasible. It was suitable for clinical use.

Carbon black (CB) nanoparticles were encapsulated by poly(vinyl alcohol) (PVA) by a simple method of coacervation. Transmission electron microscopy (TEM) images clearly demonstrated that the successful encapsulation of PVA happened at the surfaces of CB nanoparticles. The particle-size distribution measurements indicated that the diameters of the obtained PVA-encapsulated CB (CB@PVA) nanoparticles were distributed within the nanoscale dimension. This strategy avoids the complicated polymerization process involved in the counterpart of polymer-coating approaches. A TEM image of PVA-encapsulated carbon black.