Search

As core components in electric/electronic fields, dielectric materials have recently received ever‐increasing interests. Among them, polymer‐based dielectric composites have drawn ever‐increasing attentions due to their high‐temperature resistance and excellent processibility. However, state‐of‐art studies mostly focus on the modification of single‐phase filler, while the heterogeneous three phase interactions between fillers and polymer matrix are rarely studied. To fill this gap, in this study, a novel strategy of interfacial design and structural construction of three‐phase BaTiO3/rGO/polymer nanocomposites have been promoted to simultaneously build interfacial barriers between adjacent rGO nanosheets and to enhance the interfacial polarization of rGO nanosheets for improved dielectric, thermal and mechanical properties. The dielectric constant of 0.6 wt% BT/ARGO/PEI reached 644@1 kHz with a dielectric loss of only 0.218, while these values for 0.5 wt% ARGO/PEI composites are 471 and 0.489, respectively. Meanwhile, the breakdown strength almost doubled (from 48 kV·mm−1 to 87 kV·mm−1) upon the addition of BaTiO3 (BT) nanoparticles. Moreover, the introduced BT nanoparticles significantly enhanced the intermolecular frictions between different materials and contributed largely to promoted mechanical and thermal properties. We therefore speculate this work establishes a strong foundation for fabricating three heterogeneous‐phase high dielectric polymer materials with excellent dielectric, thermal and mechanical properties. Highlights: Graphene oxide was modified by APTES and reduced by L‐Ascorbic Acid.Three‐phase BT/ARGO/PEI composites showed enhanced dielectric properties.The incorporated BT nanoparticles reduced the dielectric loss.The thermal and mechanical properties of BT/ARGO/PEI composites are optimized.Interfacial interactions between different phase of materials are studied. [ABSTRACT FROM AUTHOR]

Side by side RGB OLEDs‐on‐Silicon backplane holds great promise for high brightness, high resolution and low cost Micro OLED displays. The main challenge of vacuum thermal evaporation (VTE) patterning technique is to get a submricon‐size shadow distance. Herein, we have explored the relation of shadow distance with mask‐substrate gap, as well as the relationship of shadow distance with evaporation angle. The achievements verify the possibility of manufacturing the ultra‐high resolution side by side RGB AMOLEDs with >4000ppi. The study of ultra‐high resolution evaporation patterning need to be expanded for the OLED microdisplays futures. [ABSTRACT FROM AUTHOR]

Endoscopic submucosa dissection (ESD) allows complete excision of the whole lesion, which results in a higher percentage of complete excision and an improved quality of life by minimizing the amount of excision as opposed to an endoscopic mucosal resection (EMR). Although ESD is now being carried out in the majority of hospitals, ESD's possible complications (such as trauma and perforation) have given rise to doubts about ESD practices in patients with early‐stage stomach cancer when deciding on therapy and reimbursement. This study was designed to evaluate the effectiveness and safety of ESD over EMR in treating early‐stage stomach cancer. Four main databases have been searched, including EMBASE and published. The ROBINS‐I tool suggested in the Cochrane Handbook has been applied to evaluate the quality of the chosen trials. It may better reflect the risk of bias in the included studies. The meta‐analyses were carried out with ReMan 5.3, and the results were treated with endote. Seven cohort studies have been completed. Meta analysis indicated that EMR and ESD surgery did not differ significantly from each other in terms of postoperative haemorrhage (OR, 0.76; 95%CI, 0.56,1.04 p = 0.09); EMR, however, was associated with a lower rate of postoperative perforation than ESD surgery (OR, 0.36; 95%CI, 0.24,0.54 p < 0.0001). Taking into account that ESD and EMR did not differ significantly in the risk of wound bleeding, even though the risk of perforation is not likely to result in life‐threatening illness. In the analysis of these data, however, the potential advantages of EMR might be greater than ESD. [ABSTRACT FROM AUTHOR]

The surface plasmon resonance (SPR)‐generated electric field (E‐field) intensities around a Ag nanocube (NC) before and after it is covered by a BaTiO3 (BTO) layer (BTO@Ag NC) were calculated. It was observed that the theoretical E‐field intensities were reduced on BTO@Ag NCs, thus suggesting inferior catalytic activities under visible light illumination. However, BTO@Ag NCs experimentally displayed better photocatalytic performance than that of Ag NCs under illumination at 633 nm, both in ambient argon (Ar) and in ambient air, where p‐aminothiophenol (PATP) molecules were used to probe the conversion. The mechanism can be attributed to the surface polarization of the BTO layer trigged by a SPR effect of the Ag core. The oscillation of free electrons in the Ag core aroused appearance of surface polarization charge on the ferroelectric (FE) BTO surface, which resulted in the enhanced catalytic properties of BTO@Ag NCs. Therefore, our finding may provide a novel method to enhance visible‐light responsive photocatalytic activity of wide bandgap FE materials by depositing them on plasmonic metal nanostructures. [ABSTRACT FROM AUTHOR]

With the rapid development of integrated circuits towards miniaturization and complexity, there is an urgent need for materials with low dielectric constant/loss and high processing temperatures to effectively prevent signal delay and crosstalk. With high porosity, thermal stability, and easy structural modulation, covalent organic frameworks have great potential in the field of low dielectric materials. However, the optimization of dielectric properties by modulating the conjugated/plane curvature structure of covalent organic frameworks (COFs) has rarely been reported. Accordingly, we herein innovatively prepare COF films with adjustable planar curvature, hence possessing ultralow dielectric constant (1.9 at 1 kHz), ultralow dielectric loss at 1 kHz (0.0029 at room temperature, 0.0052 at 200 °C), high thermal decomposition temperature (5 % weight loss temperature, 473 °C) and good hydrophobicity (water contact angle, 105.3°). Also, to the best of our knowledge, we are the first to report that the resulting COF film enables high surface potential (≈320 V) for one week, attributing to its intrinsic high porosity, thus presenting great potential in electret applications. Accordingly, this innovative work provides a readily available and scalable idea to prepare materials with comprehensively excellent dielectric and electret properties as well as high processing temperatures simultaneously for advanced electronic device applications. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the heat generation on yttria‐stabilized tetragonal zirconia polycrystalline (Y‐TZP) crowns during polishing with coarse and fine polishing systems at various speeds. Materials and Methods: Two polishers (coarse and fine) at three polishing speeds were investigated. Two simulation models of the first mandibular molars were prepared for full coverage Y‐TZP restorations with different reduction dimensions. Preheated water was pumped into the abutment chamber, to simulate the intrapulpal temperature and blood flow. Twelve Y‐TZP crowns (3M™ Lava™ Esthetic) were milled for each prepared tooth abutment and each cusp (n = 10) was individually ground for 30 s and polished for 2 min. Thermocouple wire was secured to the intaglio surface of the crown and linked to a data logger for recording temperature changes. Selected scanning electron microscopy (SEM) images of the treated surfaces and polishers were analyzed. The data was statistically analyzed using Prism 9. Results: The highest temperature rise was observed in the 20,000 RPM polishing speed groups for both coarse and fine polishing, and higher than the threshold value of 5.5°C for pulp damage. The Kruskal–Wallis test, revealed statistically significant differences (p <.0001) in heat generation between low (10,000 RPM) and high (20,000 RPM) polishing speeds. Conclusions: High‐speed polishing at 20,000 RPM generated the most heat over the threshold of 5.5°C, which would threaten the dental pulp. The results suggest that a cautionary approach should be taken to high‐speed intraoral polishing. Clinical Relevance: Dental clinicians should be aware of the choice of polishing systems and speeds to avoid pulp damage from intraoral polishing of Y‐TZP restorations. [ABSTRACT FROM AUTHOR]

Herein, a facile, controllable, and versatile method is reported to prepare monodisperse yolk‐shell and yolk‐multishell silica nanoparticles (NPs) with mesoporous shells by a novel selective etching strategy. The mechanism of selective etching based on fluoride‐silica chemistry is investigated in detail and thus provides a fundamentally novel principle for the fabrication of yolk‐shell NPs. Specifically, this unprecedented and versatile synthesis strategy can be used to encapsulate essentially any silica‐based, carbon‐based, metal, metal oxide, or other possible NPs. Noteworthy is that most of the yolk‐shell mesoporous silica (mSiO2) NPs are prepared for the first time. To demonstrate the major structural and compositional advantages of the designed yolk‐shell NPs, their applications in the fields of ultralow‐dielectric constant (k) materials, drug delivery systems, and catalysts were explored. In detail, the lowest k value of the prepared yolk‐shellordered mesoporous silica@mSiO2/fluorinated polybenzoxazole composite films is 2.02; The obtained yolk‐shell mSiO2/C@mSiO2/C NPs possess high hydrophilicity and pH‐responsive sensitivity; The conversion of the catalytic reaction of the designed magnetic yolk‐shell hollow Fe3O4@SiO2/Au@mSiO2 NPs at 20 min is 97% with a high conversion rate (92%) and recyclability even after 10 reuses. This innovative work lays a solid foundation for freely tailorable yolk‐shell encapsulation and will greatly stimulate more efforts devoted to relevant research and development. [ABSTRACT FROM AUTHOR]

Protein post‐translational modifications (PTMs), such as ADP‐ribosylation and phosphorylation, regulate multiple fundamental biological processes in cells. During bacterial infection, effector proteins are delivered into host cells through dedicated bacterial secretion systems and can modulate important cellular pathways by covalently modifying their host targets. These strategies enable intruding bacteria to subvert various host processes, thereby promoting their own survival and proliferation. Despite rapid expansion of our understanding of effector‐mediated PTMs in host cells, analytical measurements of these molecular events still pose significant challenges in the study of host–pathogen interactions. Nevertheless, with major technical breakthroughs in the last two decades, mass spectrometry (MS) has evolved to be a valuable tool for detecting protein PTMs and mapping modification sites. Additionally, large‐scale PTM profiling, facilitated by different enrichment strategies prior to MS analysis, allows high‐throughput screening of host enzymatic substrates of bacterial effectors. In this review, we summarize the advances in the studies of two representative PTMs (i.e., ADP‐ribosylation and phosphorylation) catalyzed by bacterial effectors during infection. Importantly, we will discuss the ever‐increasing role of MS in understanding these molecular events and how the latest MS‐based tools can aid in future studies of this booming area of pathogenic bacteria–host interactions. [ABSTRACT FROM AUTHOR]

Quasi‐2D perovskite materials have great potential for achieving high‐performance blue perovskite light‐emitting diodes (PeLEDs). Major challenges lie in the need to minimize the energy level mismatch between the blue‐emitting and the charge‐transport materials for better carrier injection, and to suppress low‐dimensional phases in quasi‐2D systems for improved radiation recombination. Here, this work introduces a subtly functionalized compound, methoxylated phenethylammonium bromide (y‐MeO‐PEABr), into the sky‐blue quasi‐2D perovskite. This approach induces an upward shift of the energy levels of the perovskite and reduces the holes injection barrier, thereby achieving a better charge balance. In addition, the introduction of large y‐MeO‐PEA+ cations effectively suppresses the formation of undesirable phases in quasi‐2D perovskites, leading to a more concentrated phase distribution and accelerated energy transfer. Specifically, the sky‐blue quasi‐2D PeLED based on 2‐MeO‐PEABr exhibits optimal device performance, obtaining a maximum external quantum efficiency of 10.85% at 486 nm. This work suggests that this method may provide a guide for designing novel organic spacer cations to obtain high‐performance blue quasi‐2D PeLEDs. [ABSTRACT FROM AUTHOR]

SUMMARY: Arabidopsis histone deacetylase HDA19 is required for gene expression programs of a large spectrum of plant developmental and stress‐responsive pathways. How this enzyme senses cellular environment to control its activity remains unclear. In this work, we show that HDA19 is post‐translationally modified by S‐nitrosylation at 4 Cysteine (Cys) residues. HDA19 S‐nitrosylation depends on the cellular nitric oxide level, which is enhanced under oxidative stress. We find that HDA19 is required for cellular redox homeostasis and plant tolerance to oxidative stress, which in turn stimulates its nuclear enrichment, S‐nitrosylation and epigenetic functions including binding to genomic targets, histone deacetylation and gene repression. The Cys137 of the protein is involved in basal and stress‐induced S‐nitrosylation, and is required for HDA19 functions in developmental, stress‐responsive and epigenetic controls. Together, these results indicate that S‐nitrosylation regulates HDA19 activity and is a mechanism of redox‐sensing for chromatin regulation of plant tolerance to stress. Significance Statement: The stress‐induced S‐nitrosylation regulates HDA19 activity to deacetylate H3K14 and to repress expression of subsets of genes under stress. [ABSTRACT FROM AUTHOR]

Structurally diverse acylations have been identified as post‐translational modifications (PTMs) on histone lysine residues, but their functions and regulations remain largely unknown. Interestingly, in nature, a lysine acylation analog, pyrrolysine, is introduced as a co‐translational modification (CTM) through genetic encoding. To explore this alternative life form, we created a model organism Saccharomyces cerevisiae containing site‐specific lysine CTMs (acetyl‐lysine, crotonyl‐lysine, or another synthetic analog) at histone H3K56 using non‐canonical amino acid mutagenesis to afford a chemically modified nucleosome in lieu of their own in vivo. We further demonstrated that acetylation of histone H3K56 partly tends to provide a more favorable chromatin environment for DNA repair in yeast compared to crotonylation and crosstalk with other PTMs differently. This study provides a potentially universal approach to decipher the consequences of different histone lysine PTMs in eukaryotes. [ABSTRACT FROM AUTHOR]

Owing to the high porosity and low thermal conductivity of organic aerogels, they have been widely used to develop lightweight heat insulation materials. However, their applications in high‐temperature environments such as in aerospace applications are usually limited by the heat resistance or ablative property of the organic matrix. In this study, we prepared a novel organic aerogel for high‐temperature insulation by the sol–gel method and freeze‐drying. The matrix is the thermosetting silicon‐containing polyarylacetylene (PSA) resin with excellent comprehensive properties, namely, high heat stability, low volatile component content, and high‐temperature ceramic performance. The obtained PSA aerogel retains the heat resistance (Td5 = 634.8°C) and ablative properties (Yr800 = 92.6%) of the PSA resin, and the internal regular macropores and high porosity (70%) result in an extremely low weight (0.1200 g cm−3), low thermal conductivity (0.039 W m−1 K−1)), and efficient heat insulation. Thus, this is an ideal material for high‐temperature insulation in the aerospace field. [ABSTRACT FROM AUTHOR]

A comprehensive study of the batch‐to‐melt (BtM) conversion process was carried out on a single high‐boron alkaline earth aluminosilicate glass composition, which is relevant to manufacturing high‐performance fiberglass for high‐end electronic applications. In the study, we used several techniques to trace the BtM process from room temperature up to 1400°C, namely isotherm batch heat‐treatment, X‐ray diffraction (XRD), hot‐stage microscopy (HSM), high‐temperature differential scanning calorimetry (DSC), and Fourier transform infrared (FT‐IR). In the BtM process, the intermediate aluminum borate phase (Al4B2O9) between 1000 and 1100°C was identified. The formation of Al4B2O9 is explained in conjunction with the dihydroxylation of kaolin. For the first time, the potential use of the FT‐IR method in studying the BtM process was demonstrated, including the dissolution of sand above 1100°C. [ABSTRACT FROM AUTHOR]

Selenium (Se) is an essential trace element in human. Recent studies of Se supplementation on the effect of Hashimoto's thyroiditis (HT) have been reported, but the exact benefit is unclear as well as the underlying immunologic mechanism. We aimed to evaluate the clinical effect of Se supplement in patients with HT, and explore the potential mechanism against thyroid autoimmunity. A prospective, randomized‑controlled study was performed in patients with HT assigned to two groups. Se‐treated group (n = 43) received selenious yeast tablet (SYT) for 6 months, whereas no treatment in control group (n = 47). The primary outcome is the change of thyroid peroxidase antibody (TPOAb) or thyroglobulin antibody (TGAb). Second, thyroid function, urinary iodine, Se, Glutathione peroxidase3 (GPx3), and Selenoprotein P1 (SePP1) levels were measured during the SYT treatment. Meanwhile, regulatory T cells (Tregs) and their subsets activated Tregs (aTregs), resting Tregs, and secreting Tregs, as well as Helios and PD‐1 expression on these cells were also detected. The results showed that SYT treatment significantly decreased TPOAb, TGAb, and thyroid stimulating hormone (TSH) levels, accompanied with the increased Se, GPx3, and SePP1, compared with the control group. Subgroup analysis revealed that subclinical HT may benefit more from this treatment in the decrease of TSH levels by interaction test. Moreover, the percentage of aTregs, Helios/Tregs, and Helios/aTregs were significantly higher in the Se‐treated group than control. In conclusion, Se supplementation may have a beneficial effect on thyroid autoantibodies and thyroid function by increasing the antioxidant activity and upregulating the activated Treg cells. [ABSTRACT FROM AUTHOR]

The temperature‐responsive bulky hydrogel with fast response rate and satisfactory mechanical property has fascinating application potential in many aspects, such as the implantable macroscale controlled drug release carrier for post‐surgical therapy; however, creating such a smart hydrogel was proven extremely challenging. Here a novel type of temperature‐responsive bulky hydrogel with ultrafast response rate and super compressible elasticity was fabricated by the fibrous freeze‐shaping technique using shortened temperature‐responsive polymer based electrospun hollow nanofibers as building blocks, followed by heat treatment for endowing the hydrogel with high stability in water. Because the hydrogel has hierarchical porous structure and its constituent nanofibers have hollow structure, which are beneficial to diffusion of its embodied water during temperature‐induced volume phase transition, its temperature‐response time is less than 30 s. In addition, the hierarchical porous structure benefits dissipation of the compression stress exerted on the hydrogel. Fluorescein isothiocyanate (FITC)‐dextran as a model biomacromolecular drug, was loaded into the shells of the hollow nanofibers during coaxial electrospinning, and the ultimately obtained nanofibrous hydrogel can release its loaded FITC‐dextran in a 'on–off' switchable fashion in response to temperature alternation between 15 and 47°C. Cell cytotoxicity test results demonstrate that the temperature‐responsive nanofibrous hydrogel is biocompatible. [ABSTRACT FROM AUTHOR]

Background: Alterations in gray matter (GM) have been recognized as playing an important role in the neurobiological mechanism underlying major depressive disorder (MDD) and antidepressant responses. However, little is known about white matter (WM) connectivity in MDD, leaving an incomplete understanding of the pathophysiology of the disorder.Purpose: To examine the functional connectivity (FC) of WM, GM, and WM-GM in MDD patients and explore the relationship between FC and antidepressant response.Study Type: Longitudinal study.Subjects: In all, 129 MDD patients and 89 healthy controls (HC).Field Strength/sequence: Whole-brain blood oxygen level-dependent (BOLD) single-shot echo planar imaging was acquired at 3.0T.Assessment: At baseline, all participants received Hamilton depression rating scale (HAMD) assessment and an fMRI scan. After 2- and 8-week antidepressant treatment, patients completed the HAMD again. The HAMD reductive rate of 2- and 8-weeks were calculated.Statistical Tests: The comparisons of age, education, HAMD scores, and FC values (false discovery rate correction) between patients and controls were calculated with a two-sample t-test. The chi-square test was employed to compare the differences of gender between these two groups. Correlations between FC and HAMD, as well as the reductive rate of HAMD, were analyzed with Pearson or Spearman correlation. Receiver operator curve analysis was performed to predict the antidepressant response.Results: Compared to HC, MDD patients exhibited widespread decreases in FC of WM-GM. Furthermore, 28 GM regions and 11 WM bundles had lower connectivity in MDD patients. At baseline, four FC of WM-GM showed negative correlations with the HAMD scores. Six FC of WM-GM correlated with the 2-week reductive rate of HAMD. Moreover, FC in GM, WM, and WM-GM also exhibited significantly positive correlations with an 8-week reductive rate of HAMD.Data Conclusion: The FC of WM-GM was decreased in MDD and may play a role in its pathophysiology and antidepressant responses.Level Of Evidence: 2.Technical Efficacy Stage: 2. [ABSTRACT FROM AUTHOR]

An amphiphilic organic cage was synthesized and used as self‐assembly synthon for the fabrication of novel functional supramolecular structures in solution. The transmission electron microscopy (TEM) results showed that this amphiphilic cage self‐assembled in aqueous solution into unilamellar nanotubes with a diameter of 29±4 nm at a concentration of 0.05 mg mL−1. Interestingly, the self‐assembly of this cage significantly enhanced the anion‐π interactions as indicated by a remarkable increasement of association constant (Ka) between Cl− and this amphiphilic cage after self‐assembly. In specific, Ka was increased from 223 M−1 for discrete cages in methanol to 6800 M−1 for aggregated cages after self‐assembly in water at the same concentration of 2.26×10−5 M. A mechanism based on a synergistic effect was proposed in order to explain this self‐assembly process through enhanced anion‐π interactions. [ABSTRACT FROM AUTHOR]

Considerable efforts have been made to increase the topological complexity of mechanically interlocked molecules over the years. Three‐dimensional catenated structures composed of two or several (usually symmetrical) cages are one representative example. However, owing to the lack of an efficient universal synthetic strategy, interlocked structures made up of dissymmetric cages are relatively rare. Since the space volume of the inner cavity of an interlocked structure is smaller than that outside it, we developed a novel synthetic approach with the voluminous reductant NaBH(OAc)3 that discriminates this space difference, and therefore selectively reduces the outer surface of a catenated dimer composed of two symmetric cages, thus yielding the corresponding catenane with dissymmetric cages. Insight into the template effect that facilitates the catenation of cages was provided by computational and experimental techniques. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Medicine & International Health is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Elevated ambient temperatures affect plant growth and substantially impact biomass and crop yield. Recent results have indicated that chromatin remodelling is critical in plant thermal responses but how histone modification dynamics affects plant thermal response has not been clearly demonstarted. Here we show that Arabidopsis histone deacetylase genes HDA9,HDA15 and HDA19 play distinct roles in plant response to elevated ambient temperature. hda9 and hda19 mutants showed a warm‐temperature‐insensitive phenotype at 27°C, whereas hda15 plants displayed a constitutive warm‐temperature‐induced phenotype at 20°C and an enhanced thermal response at 27°C. The hda19 mutation led to upregulation of genes mostly related to stress response at both 20 and 27°C. The hda15 mutation resulted in upregulation of many warm temperature‐responsive as well as metabolic genes at 20 and 27°C, while hda9 led to differential expression of a large number of genes at 20°C and impaired induction of warm‐temperature‐responsive genes at 27°C. HDA15 is associated with thermosensory mark genes at 20°C and that the association is decreased after shifting to 27°C, indicating that HDA15 is a direct repressor of plant thermal‐responsive genes at normal temperature. In addition, as hda9, the hda15 mutation also led to upregulation of many metabolic genes and accumulation of primary metabolites. Furthermore, we show that HDA15 interacts with the transcription factor HFR1 (long Hypocotyl in Far Red1) to cooperatively repress warm‐temperature response. Our study demonstrates that the histone deacetylases target to different sets of genes and play distinct roles in plant response to elevated ambient temperature. Significance Statement: Arabidopsis histone deacetylases HDA15, HDA9 and HDA19 have distinct functions in genome‐wide gene expression and plant response to elevated ambient temperature. HDA15 is a direct repressor of high‐temperature‐responsive genes and interacts with transcription factor HFR1, whereas HDA9 and HDA19 promote plant thermal response likely through indirect mechanisms. [ABSTRACT FROM AUTHOR]

Top emitting white organic light emitting diodes (WOLEDs) hold great promise for high brightness and high resolution active matrix OLED displays. One key challenge of high‐performance top emitting WOLEDs is the availability of top electrodes with superior optical, electrical properties. Herein, we demonstrate the application of the dielectric/metal/dielectric structure consisting of a titanium dioxide WO3/Ag/WO3 stack as the transparent top cathode on organic light‐emitting diodes (OLEDs). Better performance than that of the normally used semi‐transparent Mg:Ag cathode was obtain from the top emitting WOLEDs with the DMD cathode. Moreover, DMD device not only show bright emission similar to that of the IZO cathode device, but also enduring no damage in the device fabrication. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to develop an accurate and robust phase‐unwrapping method that works effectively under severe noise, rapid‐varying phase, and disconnected regions for water–fat Dixon MRI. Methods: The proposed method first segments the phase map into blocks by automatically detecting phase jumps, and then clusters the pixels near phase jumps into residual pixels. Thereafter, the proposed method sequentially performs intrablock, interblock, and residual‐pixel unwrapping using the local surface fitting approach. To address intrablock wraps, the proposed method segments each block into subblocks using the phase partition approach and then performs inter‐subblock unwrapping using a block‐growing approach. The phase derivative variance is used as the quality criterion to determine the region‐growing path of residual pixels. The performance of the proposed method was evaluated on simulation and in vivo Dixon data. Results: The proposed method obtained accurate phase‐unwrapping results in the simulation experiment with severe noise, rapid‐varying phase, and disconnected regions, and the mean and SD error ratio was 0.26 ± 0.07%. For 505 in vivo knee and ankle images, the total water–fat swap ratio by the proposed method was 1.78%, whereas those by phase region expanding labeler for unwrapping discrete estimates and clustering and local surface fitting were 38.42% and 7.72%, respectively. Conclusion: The proposed method achieves accurate and robust performance in phase unwrapping and can benefit phase‐related MRI applications such as Dixon water–fat separation. [ABSTRACT FROM AUTHOR]

Purpose: To improve liver R 2 * mapping by incorporating adaptive neighborhood regularization into pixel‐wise curve fitting. Methods: Magnetic resonance imaging R 2 * mapping remains challenging because of the serial images with low signal‐to‐noise ratio. In this study, we proposed to exploit the neighboring pixels as regularization terms and adaptively determine the regularization parameters according to the interpixel signal similarity. The proposed algorithm, called the pixel‐wise curve fitting with adaptive neighborhood regularization (PCANR), was compared with the conventional nonlinear least squares (NLS) and nonlocal means filter‐based NLS algorithms on simulated, phantom, and in vivo data. Results: Visually, the PCANR algorithm generates R 2 * maps with significantly reduced noise and well‐preserved tiny structures. Quantitatively, the PCANR algorithm produces R 2 * maps with lower root mean square errors at varying R 2 * values and signal‐to‐noise‐ratio levels compared with the NLS and nonlocal means filter‐based NLS algorithms. For the high R 2 * values under low signal‐to‐noise‐ratio levels, the PCANR algorithm outperforms the NLS and nonlocal means filter‐based NLS algorithms in the accuracy and precision, in terms of mean and standard deviation of R 2 * measurements in selected region of interests, respectively. Conclusions: The PCANR algorithm can reduce the effect of noise on liver R 2 * mapping, and the improved measurement precision will benefit the assessment of hepatic iron in clinical practice. Magn Reson Med 80:792–801, 2018. © 2018 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Abstract: Apatinib is a small‐molecule tyrosine kinase inhibitor that has been approved for the treatment of patients with advanced‐stage gastric cancer or gastroesophageal junction cancer who have progressed or recurred after at least 2 kinds of systemic chemotherapy. In vitro data indicate that cytochrome P450 (CYP) 3A4 is the primary CYP isoenzyme involved in the metabolism of apatinib. Pharmacokinetic drug–drug interactions of apatinib and (1) a CYP3A4 inducer (rifampin) or (2) a CYP3A inhibitor (itraconazole) were clinically evaluated in healthy volunteers. Compared with the single administration of apatinib, its coadministration with rifampin resulted in a 5.6‐fold plasma clearance (CL/F) and 83% decrease in plasma AUC0–t of apatinib. By contrast, coadministration with itraconazole reduced the CL/F of apatinib by 40% and increased its AUC0–t by 75%. In summary, a strong CYP3A4 inducer (rifampin) had a strong effect (>5‐fold) on the clinical pharmacokinetics of apatinib, whereas a strong CYP3A inhibitor (itraconazole 100 mg once a day) had a weak effect (1.25‐ to 2‐fold). Whether these effects are of clinical significance needs further research and information about the exposure–safety and exposure–efficacy relationship of apatinib. [ABSTRACT FROM AUTHOR]

Purpose To develop and evaluate a novel 2D phase-unwrapping method that works robustly in the presence of severe noise, rapid phase changes, and disconnected regions. Theory and Methods The MR phase map usually varies rapidly in regions adjacent to wraps. In contrast, the phasors can vary slowly, especially in regions distant from tissue boundaries. Based on this observation, this paper develops a phase-unwrapping method by using a pixel clustering and local surface fitting (CLOSE) approach to exploit different local variation characteristics between the phase and phasor data. The CLOSE approach classifies pixels into easy-to-unwrap blocks and difficult-to-unwrap residual pixels first, and then sequentially performs intrablock, interblock, and residual-pixel phase unwrapping by a region-growing surface-fitting method. The CLOSE method was evaluated on simulation and in vivo water-fat Dixon data, and was compared with phase region expanding labeler for unwrapping discrete estimates (PRELUDE). Results In the simulation experiment, the mean error ratio by CLOSE was less than 1.50%, even in areas with signal-to-noise ratio equal to 0.5, phase changes larger than π, and disconnected regions. For 350 in vivo knee and ankle images, the water-fat swap ratio of CLOSE was 4.29%, whereas that of PRELUDE was 25.71%. Conclusions The CLOSE approach can correctly unwrap phase with high robustness, and benefit MRI applications that require phase unwrapping. Magn Reson Med 79:515-528, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

ABSTRACT Monodisperse Au@Ag bimetallic nanorods (Au@AgNRs) with gold nanorod core and silver shell were introduced into the shells of the thermoresponsive nanofibers with core-shell structure by coaxial electrospinning technique using poly( N-isopropylacrylamide- co- N-hydroxymethylacrylamide) aqueous solution as core fluid and its Au@AgNRs mixture as shell fluid, followed by heat treatment. Their core-shell structure and the oriented alignment of the Au@AgNRs embedded within their shells along their axes were confirmed by transmission electron microscopy observation. The produced composite nanofibrous membrane has high stability in aqueous medium and more remarkable and faster thermoresponsiveness than our previously reported composite nanofibrous membrane with homogeneous Au@AgNRs distribution inside its constituent nanofibers. The smart composite nanofibrous membrane as a free-standing surface enhanced Raman spectroscopy substrate with temperature-dependent surface enhanced Raman spectroscopy efficiency from 25 to 50 °C and good reproducibility is able to be used to detect 10−14 mol/L 4-mercaptobenzoic acid in aqueous solution at 50 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45375. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) loaded thermoresponsive nanofibrous hydrogel is fabricated by electrospinning the aqueous solution containing the metal nanoparticles and poly(( N-isopropylacrylamide)-co-( N-hydroxymethylacrylamide)) copolymer, followed by heat treatment. To avoid negative effect of the stabilizer or the residual reductant on their performances, the AgNPs of less than 5 nm size are synthesized through reducing Ag+ ions in the spinning solution by UV irradiation. The prepared nanofibrous hydrogel with desirable stability in aqueous medium has significant thermoresponsive property, and can reach its swelling or deswelling equilibrium state within 15 s with the medium temperature changing between 25 and 50 °C alternately. The smart nanofibrous hydrogel as a dip-catalyst has the catalysis for the reduction of 4-nitrothiophenol to 4-aminothiophenol by NaBH4, and its catalytic activity can be rapidly tuned by temperature. Moreover, it can be facilely recycled from the reaction system at least four times, without any loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

To ensure the safety and quality of food ingredients, especially meat and dairy products, a high-throughput, rapid and sensitive method to detect Listeria monocytogenes ( LM) is always on a high demand. In this work, a specific induction method to enrich and detect LM based on fluorescence immunochromatographic assay ( FICA) combined with immunomagnetic separation ( IMS) techniques has been developed. The immunomagnetic-beads ( IM) beads were obtained through functionalised magnetic microspheres and the conjugated reaction between the carboxyl on beads surface and amino groups of antibody. The prepared IM-beads could be used for rapidly enriching pathogenic bacteria with fewer steps, resulting in a high specificity for four pathogenic serotypes and about a 40-fold improvement of detection limit compared with FICA only. In addition, this method was successfully applied in LM detection in sausage, pork and milk samples with a potential for further application in rapid on-site detection of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

The conserved cAMP-dependent protein kinase (PKA) plays critical roles in the regulation of morphological transitions and virulence in the human fungal pathogen Candida albicans. It has long been thought that the PKA catalytic subunit is essential for cell viability in this fungus. Paradoxically, the single adenylyl cyclase-encoding gene, CYR1, which is required for the production of cAMP in C. albicans, is not essential for cell growth. Here, a double mutant of TPK1 and TPK2 ( tpk2/tpk2 tpk1/tpk1, t2t1), which encode two isoforms of the PKA catalytic subunit was successfully generated, suggesting that this subunit is not essential for cell viability. Inactivation of the PKA catalytic subunit blocked filamentation and dramatically attenuated white-to-opaque switching, but promoted sexual mating. Comparative transcriptomic analyses demonstrated that the t2t1 and cyr1/cyr1 mutants exhibited similar global gene expression profiles. Compared with the WT strain, the general transcriptional activity and metabolism were significantly decreased in both the t2t1 and cyr1/cyr1 mutants. Using combined phosphoproteomic and bioinformatic analyses, we identified 181 potential PKA phosphorylation targets, which represent 148 unique proteins involved in a wide spectrum of biological processes. The study sheds new insights into the global regulatory features of the cAMP/PKA pathway in C. albicans. [ABSTRACT FROM AUTHOR]

In this prospective study, conducted in China where providers have traditionally been paid fee-for-service, and where drug spending is high and irrational drug prescribing common, township health centers in two counties were assigned to two groups: in one fee-for-service was replaced by a capitated global budget (CGB); in the other by a mix of CGB and pay-for-performance. In the latter, 20% of the CGB was withheld each quarter, with the amount returned depending on points deducted for failure to meet performance targets. Outcomes studied included indicators of rational drug prescribing and prescription cost. Impacts were assessed using differences-in-differences, because political interference led to non-random assignment across the two groups. The combination of capitated global budget and pay-for-performance reduced irrational prescribing substantially relative to capitated global budget but only in the county that started above the penalty targets. Endline rates were still appreciable, however, and no effects were found in either county on out-of-pocket spending. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The organic-inorganic hybrid nanocomposites from high-impact polystyrene/octavinyl polyhedral oligomeric silsesquioxane (HIPS/POSS) containing various percentages of POSS were prepared by free radical polymerization and characterized by Fourier transform infrared spectroscopy (FTIR), ³H-NMR, thermal gravity analysis (TGA), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The octavinyl POSS has formed covalent bond connected PS-POSS hybrid with polystyrene. POSS can well disperse in the composites at the composition of 0.5 and 1 wt%. The mechanical properties and thermostability of HIPS/ POSS nanocomposites were significantly improved. The tensile strength, the izod impact strength, and the elongation at break of the nanocomposite containing 1 wt% of POSS was increased, respectively, by 15.73%, 75.62%, and 72.71% in comparison with pristine HIPS. The thermal decomposition temperature of HIPS/POSS (1 wt% of POSS) was 33°C higher than that of pristine HIPS. The HIPS/POSS nanocomposites showed great potential for applications in many fields, such as electric appliance and automotive trim. [ABSTRACT FROM AUTHOR]

Purpose To develop and evaluate a novel method of generalized auto-calibrating partially parallel acquisition (GRAPPA) with spatially varying calibration of self-constraint for parallel magnetic resonance imaging (MRI) reconstruction. Theory and Methods The conventional GRAPPA independently estimates each missing sample with adjacent acquired data over multiple coils, thereby ignoring correlations inside missing data. Self-constrained methods can exploit correlations inside missing data by imposing linear dependence within full neighborhood kernels and showing improved reconstruction compared with GRAPPA. However, self-constraint kernels are currently calibrated by using auto-calibration signals. Thus, they may be suboptimal for reconstructing outer k-space because of spatially varying correlations. This study proposes a novel GRAPPA method with separate self-constraints (SSC-GRAPPA). In this method, the spatially varying self-constraint coefficients are adaptively calibrated by separately exploiting correlations inside missing and acquired data in the outer k-space. Both phantom and in vivo imaging experiments were conducted with retrospective undersampling to evaluate the performance of the proposed method. Results Compared with GRAPPA and self-constrained GRAPPA, the proposed SSC-GRAPPA generates images with reduced artifacts and noise. Conclusion The proposed method provides an effective and efficient approach to improve parallel MRI reconstruction, and has potential to benefit routine clinical practice in the future. Magn Reson Med 74:1057-1069, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Poly (p-phenylene benzobisoxazole)/carbon nanotube (PBO/CNTs) composites have already been experimentally synthesized with the outstanding mechanical and electrical properties. Carboxylic carbon nanotubes (CNT-COOH), obtained by acid treatment, can better disperse than pristine nanotubes in PBO matrix, which is estimated due to hydrogen bonds between them and investigated by Quantum Mechanics/Molecular mechanics (QM/MM) calculation. In the dynamic simulation, the N atoms in PBO and H atoms in carboxyl can be close enough to form hydrogen bond and the angle of oxygen-hydrogen-nitrogen (OHN) is obtuse, suitable for hydrogen bond. Further more, the electrostatic potential (ESP) and ESP fit charge of N and O atoms in PBO has been measured by Density Functional Theory (DFT) calculation to prove that hydrogen bonds can be formed only by N atoms in the heterocycle of PBO and H atoms in carboxyl of the CNT-COOH. POLYM. COMPOS., 36:1454-1461, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT We report our work for preparing cross-linked polyimide via a series of imide functional benzoxazine resins as precursors. The structures of synthesized monomers have been confirmed by 1H NMR and FT-IR. Among this class of benzoxazine monomers, the ortho-imide functional benzoxazine resins show useful features both in the synthesis of benzoxazine monomers and the properties of the corresponding thermosets. For the cross-linked polyimides based on ortho-imide functional benzoxazine, an additional route is adopted to form a more thermally stable cross-linked polybenzoxazole with the release of carbon dioxide. The ortho-imide functional benzoxazine resins show the possibility to form high performance and even super high performance thermosets with low cost and easy processability. The thermal properties are evaluated by DSC and TGA. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1330-1338 [ABSTRACT FROM AUTHOR]

Reducing liquid surface tension is widely used to increase the efficiency of the centrifugal dehydration in textile wet processing. However, increasing the dehydration efficiency by decreasing fabric surface energy is seldom studied. In this work, the impact of in situ fabric surface energy on residual moisture content (RMC) of fabrics in the dehydration processes was investigated. Different types of fluorocarbon surfactants including cationic, anionic, nonionic and amphoteric were adopted as additives in this study. The liquid surface tension and RMC were efficiently decreased when fluorocarbon surfactants were used. Notably, a cationic fluorocarbon surfactant displays similar surface tension but distinct dehydration efficiency. The in situ fabric surface energy was evaluated by measuring the n-octane contact angle on the cotton fabric surface under the surfactant solution using the captive bubble method. It was found that the cationic fluorocarbon surfactant system gave the lowest fabric surface energy, which was probably because cationic fluorocarbon surfactants are easier to adsorb onto the surface of cotton fabric to form a fluorocarbon layer. The chemical composition (F, C and O) analysis of the cotton fabric surface by X-ray photoelectron spectroscopy confirms the hypothesis. [ABSTRACT FROM AUTHOR]

A series of magnetic fluorinated polybenzobisoxazole (6FPBO)/silica-coated Fe3O4 magnetic nanoparticles composites were synthesized through in-situ polymerization. The structure and morphology of the obtained nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, and scanning electronic microscope (SEM). The SEM images indicated that the crosslinking structure is formed in magnetic 6FPBO nanocomposites. The magnetic and electromagnetic properties of magnetic 6FPBO nanocomposites in the 2-18 GHz frequency range were characterized by vibration sample magnetometer and vector network analyzer, respectively. The calculated reflection loss of the as-prepared magnetic 6FPBO nanocomposites showed that the best microwave absorption reached to −20 dB at 17 GHz with a matching thickness of 3.00 mm. POLYM. COMPOS., 36:884-891, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In view of the low solubility of thiourea dioxide in water and its inertia to most chemical reagents, a novel non-aqueous medium, decamethylcyclopentasiloxane, was introduced to replace water in the grinding process for better dispersibility and discharge stability. In this study, the effects of different grinding methods on the particle size distribution and surface appearance of thiourea dioxide were studied. The influences of aqueous and decamethylcyclopentasiloxane media on the discharge stability of thiourea dioxide in discharge paste were compared. The whiteness, handle, and the tensile strength of the discharge-printed fabric were evaluated. The results showed that the wet grinding process endowed thiourea dioxide with smaller particle sizes and narrower size distributions in the presence of dispersants. Decamethylcyclopentasiloxane as a non-aqueous medium was beneficial in maintaining good discharge stability of thiourea dioxide for a longer time. The fabrics discharged by the prepared thiourea dioxide printing paste had favourable whiteness, good handle, and acceptable tensile strength. [ABSTRACT FROM AUTHOR]

In the interaction between plant and microbial pathogens, reactive oxygen species ( ROS) rapidly accumulate upon pathogen recognition at the infection site and play a central role in plant defence. However, the mechanisms that plant pathogens use to counteract ROS are still poorly understood especially in oomycetes, filamentous organisms that evolved independently from fungi. ROS detoxification depends on transcription factors ( TFs) that are highly conserved in fungi but much less conserved in oomycetes. In this study, we identified the TF Ps HSF1 that acts as a modulator of the oxidative stress response in the soybean stem and root rot pathogen P hytophthora sojae. We found that Ps HSF1 is critical for pathogenicity in P . sojae by detoxifying the plant oxidative burst. ROS produced in plant defence can be detoxified by extracellular peroxidases and laccases which might be regulated by Ps HSF1. Our study extends the understanding of ROS detoxification mechanism mediated by a heat shock TF in oomycetes. [ABSTRACT FROM AUTHOR]

Purpose Fitting the measured decay signal to the first moment in the presence of noncentral chi noise (M1NCM) can correctly address the effect of noise on the effective transverse relaxation rate (R2*) relaxometry of iron loaded liver. However, this method requires intensive computation, which restricts its application to R2* mapping. This work aims to develop a rapid implementation of the M1NCM method for R2* mapping. Methods The computation of the confluent hypergeometric function in the M1NCM model was approximated using cubic spline interpolation with breakpoints and coefficients precalculated and stored in a look-up table (M1NCM-LUT). The performance of the proposed M1NCM-LUT method was evaluated through simulation and based on in vivo liver R2* relaxometry data. Results In both simulation and in vivo studies, the maximum absolute difference between R2* maps generated by the M1NCM and M1NCM-LUT methods was nearly 10−3 s−1 or less, and the M1NCM-LUT method obtained a R2* map in approximately 1 s and achieved an acceleration of approximately five orders of magnitude. Conclusion The proposed M1NCM-LUT method can significantly increase the speed of the liver R2* mapping using the M1NCM model. This development is important in promoting application of this R2* mapping technique for tissue iron quantification. Magn Reson Med 73:865-871, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In this study, monodisperse bimetallic nanorods with gold (Au) nanorod core and silver (Ag) shell (Au@AgNRs) were synthesized through seed-mediated growth process by reduction of AgNO3 using Au nanorods with narrow size and shape distribution as seeds. With increasing the used amount of AgNO3, the Ag shell thickness of their lateral facets is raised faster than that of their two tips, leading to a decrease of their aspect ratios. Four plasmon bands are observable on the extinction spectra of Au@AgNRs, which are attributed to the longitudinal dipolar plasmon mode, transverse dipolar plasmon mode, and octupolar plasmon mode of the core-shell structured bimetallic nanorods, respectively. As their Ag shell thickness increases, their longitudinal plasmon band blue-shifts notably with the transverse plasmon band blue-shifting and the two octupolar plasmon bands red-shifting slightly, due to the decrease of their aspect ratios and enhancement of Ag plasmon resonance contribution. When used as surface-enhanced Raman scattering (SERS) substrate for probing minute amounts of 4-mercaptobenzoic acid in aqueous solution, Au@AgNRs have much stronger SERS activity than Au nanorods, and the obtained Raman signals are highly reproducible arising from their excellent monodispersity. Their SERS activity is remarkably increased with their Ag shell thickness thanks to the enhancing surface electric field and the chemical enhancement associated with electronic ligand effect. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new crosslinking reaction between benzoxazine and benzoxazole was discovered by investigating the heat ‐ curing reaction of bisphenol A/aniline ‐ based benzoxazine monomer with a polybenzoxazole (PBO) model compound. This new crosslinking reaction provides a facile and straightforward method for the preparation of high ‐ performance crosslinked PBO/polybenzoxazine copolymer composites. [ABSTRACT FROM AUTHOR]

An in vivo study of Strychnos alkaloids metabolites in rats by ultra high performance liquid chromatography with linear ion trap Orbitrap MS is reported for the first time. Two major Strychnos alkaloids compounds including strychnine and brucine were investigated. To obtain optimal extraction efficiency, samples were pretreated by using an SPE plate. The structures of metabolites and their fragment ions were characterized based on the accurate mass and MS n data. Forty-seven metabolites were identified in rat urine, of which 25 were reported for the first time. Four new metabolism pathways were proposed on the basis of the identified metabolites. This study provides a practical approach for rapidly identifying complicated metabolites, a methodology that could be widely applied not only in forensic and clinically toxicological relevant cases, but also for the structural characterization of metabolites of other compounds. [ABSTRACT FROM AUTHOR]

Zinc blende ZnSe longitudinal twinning nanowires and a sandwich structure with the wurtzite ZnSe inserting into the zinc blende ZnSe longitudinal twinning nanowires are fabricated via a simple thermal evaporation method. The high-resolution transmission electron microscope images of the two types of nanowires match well with simulated atomic models of them. The growth of them might be caused by the crystal plane slip during the phase transformation process between the wurtzite and the zinc blende ZnSe nanowire. The vibrating and luminescence properties of the as-grown longitudinal twinning nanowire are investigated by room-temperature Raman and low-temperature (10 K) photoluminescence spectroscopy, respectively. The electrical transport properties of the two types of longitudinal twinning ZnSe nanowires and the monocrystal ZnSe nanowires were compared using in situ measurement in transmission electron microscope. [ABSTRACT FROM AUTHOR]

ABSTRACT Automotive friction materials reinforced by home-made poly ( p-phenylene benzobisoxazole) (PBO) pulp (fibrillated organic fibers) were prepared through compression molding. The friction and wear behaviors of the obtained composite materials were evaluated using a constant rotating speed type friction tester. The PBO pulp content and the testing loads showed clear influence on the tribological properties of the composites. Friction stability, wear rate, and morphology of sliding surfaces were carefully examined to investigate the effect of the pulp ingredient in the friction materials. Scanning electron microscopy was employed to study the morphology of the surface and wear particles. The significant wear reduction was achieved when the mass fraction of PBO pulp was 3%. Wear rates of the composites with 3% PBO pulp were measured over a load range from 0.3 to 1 MPa at different temperatures. The results pointed to two facts: (1) the wear rate of the friction material increased linearly with load at low temperature (below 200°C); (2) wear status varied with the testing loads at high temperature (above 250°C). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4032-4039, 2013 [ABSTRACT FROM AUTHOR]