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Inflammatory myofibroblastic tumors (IMTs) are rare. They are characterized by myofibroblastic spindle cell proliferation with a varying degree of inflammatory cell infiltration. IMT can occur in any anatomic location but has been reported in the lung, mesentery, and omentum, mainly in children or young adults. It rarely occurs in the pancreas and is often difficult to distinguish from other tumors, including some malignant ones. Therefore, it can be challenging to make a radiological diagnosis of IMT. Here, we present a case of IMT that occurred in the pancreas head of a middle-aged female. The patient’s ultrasonography, computed tomography, and magnetic resonance imaging findings are presented along with a review of the literature. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether reduced radiation dose abdominal CT images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V) compromise the depiction of clinically competent features when compared with the currently used routine radiation dose CT images reconstructed with ASIR. Methods: 27 consecutive patients (mean body mass index: 23.55 kg m-2 underwent CT of the abdomen at two time points. At the first time point, abdominal CT was scanned at 21.45 noise index levels of automatic current modulation at 120 kV. Images were reconstructed with 40% ASIR, the routine protocol of Dong-A University Hospital. At the second time point, follow-up scans were performed at 30 noise index levels. Images were reconstructed with filtered back projection (FBP), 40% ASIR, 30% ASIR-V, 50% ASIR-V and 70% ASIR-V for the reduced radiation dose. Both quantitative and qualitative analyses of image quality were conducted. The CT dose index was also recorded. Results: At the follow-up study, the mean dose reduction relative to the currently used common radiation dose was 35.37% (range: 19-49%). The overall subjective image quality and diagnostic acceptability of the 50% ASIR-V scores at the reduced radiation dose were nearly identical to those recorded when using the initial routine-dose CT with 40% ASIR. Subjective ratings of the qualitative analysis revealed that of all reduced radiation dose CT series reconstructed, 30% ASIR-V and 50% ASIR-V were associated with higher image quality with lower noise and artefacts as well as good sharpness when compared with 40% ASIR and FBP. However, the sharpness score at 70% ASIR-V was considered to be worse than that at 40% ASIR. Objective image noise for 50% ASIR-V was 34.24% and 46.34% which was lower than 40% ASIR and FBP. Conclusion: Abdominal CT images reconstructed with ASIR-V facilitate radiation dose reductions of to 35% when compared with the ASIR. Advances in knowledge: This study represents the first clinical research experiment to use ASIR-V, the newest version of iterative reconstruction. Use of the ASIR-V algorithm decreased image noise and increased image quality when compared with the ASIR and FBP methods. These results suggest that high-quality low-dose CT may represent a new clinical option. [ABSTRACT FROM AUTHOR]

We describe a versatile approach for preparing flash memory devices composed of polyelectrolyte/gold nanoparticle multilayer films. Anionic gold nanoparticles were used as the charge storage elements, and poly(allylamine)/poly(styrenesulfonate) multilayers deposited onto hafnium oxide (HfO2)-coated silicon substrates formed the insulating layers. The top contact was formed by depositing HfO2 and platinum. In this study, we investigated the effect of increasing the number of polyelectrolyte and gold nanoparticle layers on memory performance, including the size of the memory window (the critical voltage difference between the ‘programmed’ and ‘erased’ states of the devices) and programming speed. We observed a maximum memory window of about 1.8 V, with a stored electron density of 4.2 × 1012 cm−2 in the gold nanoparticle layers, when the devices consist of three polyelectrolyte/gold nanoparticle layers. The reported approach offers new opportunities to prepare nanostructured polyelectrolyte/gold nanoparticle-based memory devices with tailored performance. [ABSTRACT FROM AUTHOR]

Thermally stable nanoporous organosilicate thin films were realized by the microphase separation of pore-generating polymers mixed with an organosilicate matrix to be antireflective coatings (ARCs), for which a thin film with a refractive index (n) of 1.23 for zero reflection is required. The refractive index of such nanoporous organosilicate films can be tuned from 1.39 down to 1.23 by incorporating nanopores within the films. With a nanoporous single layer with n∼ 1.23, the light transmittance of the glass above 99.8% was achieved in the visible range ( ∼ 550 nm). To overcome the limitation on the narrow wavelength for high transmittance imposed by a single antireflective nanoporous thin film, bilayer thin films with different refractive indices were prepared by placing a high refractive index layer with a refractive index of 1.45 below the nanoporous thin film. UV−vis transmittance of a glass coated with the bilayer films was compared with nanoporous single-layer films and it is demonstrated that the novel broadband antireflection coatings in a wide range of visible wavelength can be easily obtained by the organosilicate bilayer thin films described in this study. Also, ARCs developed in this study demonstrate excellent AR durability owing to the hydrophobic nature of the organosilicate matrix. [ABSTRACT FROM AUTHOR]

We introduce a novel and versatile approach for preparing self-assembled nanoporous multilayered films with tunable optical properties. Protonated polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) and anionic polystyrene-block-poly(acrylic acid) (PS-b-PAA) block copolymer micelles (BCM) were used as building blocks for the layer-by-layer assembly of BCM multilayer films. BCM film growth is governed by electrostatic and hydrogen-bonding interactions between the opposite BCMs. Both film porosity and film thickness are dependent upon the charge density of the micelles, with the porosity of the film controlled by the solution pH and the molecular weight (Mw) of the constituents. PS7K-b-P4VP28K/PS2K-b-PAA8K films prepared at pH 4 (for PSTK-b-P4VP28K) and pH 6 (for PS2K-b-PAA8K) are highly nanoporous and antireflective. In contrast, PS7K-b-P4VP28K/PS2K-b-PAA8K films assembled at pH 4/4 show a relatively dense surface morphology due to the decreased charge density of PS2K-b-PAAsK. Films formed from BCMs with increased PS block and decreased hydrophilic block (P4VP or PAA) size (e.g., PS36K-b-P4VP12K/PS16K-b-PAA4K at pH 4/4) were also nanoporous. This is attributed to a decrease in interdigitation between the adjacent corona shells of the low Mw BCMs, thus creating more void space between the micelles. Multilayer films with antireflective and photochromic properties were obtained by incorporating a water-insoluble photochromic dye (spiropyran) into the hydrophobic PS core of the BCMs assembled in the films. The optical properties of these films can be modulated by UV irradiation to selectively and reversibly control the transmission of light. Light transmission of higher than 99% was observed with accompanying photochromism in the (PS7K-b-P4VP28K/PS2K-b-PAA8K) multilayer films assembled at pH 4/6. Our approach highlights the potential to incorporate a range of materials, ranging from conventional hydrophilic materials with specific interactions to hydrophobic compounds, into the assembled BCMs to yield multifunctional nanoporous films. [ABSTRACT FROM AUTHOR]

The article reports the formation of multilayer films comprising nanoblended layers of both weak and strong polyanions, alternately deposited with the polycation, poly-allylamine hydrochloride. This weak/strong polyectrolyte (PE) combination was chosen because of the recent interest generated by multilayer films containing weak PEs, which is largely attributed to their pH-dependent characteristics. The current work is significant because it demonstrates that nanoblended solutions comprising both weak and strong polyanions can be used to exert control over multilayer film properties, such as the film thickness, composition, morphology, and pH stability. Controlling these properties is important for many of the potential applications of PE multilayer films.

Organic field-effect transistor (OFET) memories have rapidly evolved from low-cost and flexible electronics with relatively low-memory capacities to memory devices that require high-capacity memory such as smart memory cards or solid-state hard drives. Here, we report the high-capacity OFET memories based on the multilayer stacking of densely packed hydrophobic metal NP layers in place of the traditional transistor memory systems based on a single charge trapping layer. We demonstrated that the memory performances of devices could be significantly enhanced by controlling the adsorption isotherm behavior, multilayer stacking structure and hydrophobicity of the metal NPs. For this study, tetraoctylammonium (TOA)-stabilized Au nanoparticles (TOA-AuNPs) were consecutively layer-by-layer (LbL) assembled with an amine-functionalized poly(amidoamine) dendrimer (PAD). The formed (PAD/TOA-AuNP)n films were used as a multilayer stacked charge trapping layer at the interface between the tunneling dielectric layer and the SiO2 gate dielectric layer. For a single AuNP layer (i.e. PAD/TOA-AuNP)1) with a number density of 1.82 × 1012 cm−2, the memory window of the OFET memory device was measured to be approximately 97 V. The multilayer stacked OFET memory devices prepared with four AuNP layers exhibited excellent programmable memory properties (i.e. a large memory window (ΔVth) exceeding 145 V, a fast switching speed (1 μs), a high program/erase (P/E) current ratio (greater than 106) and good electrical reliability) during writing and erasing over a relatively short time scale under an operation voltage of 100 V applied at the gate. [ABSTRACT FROM AUTHOR]

Ciliated foregut cyst is a relatively rare disease; thus, most reports are in the form of case studies. This benign cyst is usually found in the mediastinum and account for approximately 20% of all mediastinal masses. However, it is rarely found in the hepatobiliary and peripancreatic regions. Approximately 20 cases of ciliated foregut cysts involving the pancreas have been reported in the Enlgish literature. Here, we present a case of ciliated foregut cyst that occurred in the tail of the pancreas in a 29-yearold female. The patient's ultrasonography, CT, and MRI findings are presented, along with a review of the literature. [ABSTRACT FROM AUTHOR]

Aim: This study's aimwas to determine the accuracy of the spleen stiffness value acquired using acoustic radiation force impulse (ARFI) technology, to predict the presence of esophageal varices (EVs) in patients with liver cirrhosis of various etiologies. Material and Methods: Of the 366 enrolled patients, 192 had hepatitis B virus, 74 had hepatitis C virus, and 100 had alcohol-related cirrhosis. All patients underwent biochemical tests, gastrointestinal endoscopy, and liver and spleen elastography by ARFI. We evaluated the correlation between the presence of EVs and factors including liver and spleen stiffness measured by ARFI, biochemical tests, and other noninvasive measurements, such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), platelet count (PLT), spleen diameter (SD), PLT to SD ratio, AST to ALT ratio (AAR) score, the AST to PLT ratio index (APRI) score. Results: A univariate analysis revealed that the AAR score, APRI score, PLT, PLT/SD ratio, and spleen elastography variables were all independently associated with EVs (p<0.05). On multivariate analysis, only spleen elastography was associated with EVs (p=0.001). However, in cases of alcohol-induced liver cirrhosis, spleen stiffness was not reliable for the prediction of EVs. Conclusion: Spleen elastography measured using ARFI may serve as a non-invasive method for determining the presence of EVs. However, it is not an appropriate predictor for EVs in alcoholic cirrhosis. [ABSTRACT FROM AUTHOR]

Background/Aims: The purpose of this study was to as-sess the value of acoustic radiation force impulse (ARFI) for predicting the extent of radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) by correlating the elastic-ity of HCC and peritumoral parenchyma (as measured by ARFI) with the extent of ablation determined by computed tomography (CT). Methods: From September 2009 to June 2011, 158 patients underwent RFA ablation for HCC (single, ≤3 cm). We evaluated the data of a total of 38 prospectively enrolled patients who underwent both ARFI imaging and contrast-enhanced CT after one session of 12 minutes of RFA without a change in needle position. The ARFI imaging indices, including the mean shear wave velocity (SWV) of HCC, mean SWV of the peritumoral parenchyma and tumor size, were evaluated to determine the statistical correlation with RFA extent after one session of 12 minutes of RFA. Results: A stiffer liver parenchyma in patients with cirrhosis results in a smaller ablation zone. Conclusions: SWV of ARFI in liver parenchyma was well correlated with RFA extent. After evaluating the correlation between ARFI and RFA extent, we suggest that the SWV in liver parenchyma might be a non-invasive supplementary tool for predicting the extent of RFA. [ABSTRACT FROM AUTHOR]

Two different kinds of organic polyelectrolyte (PE)/inorganic silicate nanolaminates carrying dissimilar interfacial adhesion between the organic and the inorganic layers were prepared using the layer-by-layer self-assembly. To investigate the mechanical behavior of the prepared hybrid films, apparent modulus (E′), hardness (H), and crack length were measured by depth-sensing nanoindentation as well as a microVickers experiment. The fracture toughness of the hybrid films was then calculated based on the measured mechanical values. In the case of forming strong interfacial adhesion between the organic and the inorganic layers (A series), the fracture toughness and the crack resistance of hybrid multilayer films were significantly improved as a result of the redistribution of stress concentration and the dissipation of fracture energy by the plasticity of organic PE layers. On the other hand, samples with relatively low interfacial adhesion between the organic and the inorganic layers (T series) had little effect on the improvement of fracture toughness of the hybrid films. [ABSTRACT FROM AUTHOR]

A new method is introduced to build organic/organic multilayer films composed of cationic poly(allylamine hydrochloride) (PAH) and negatively-charged poly(sodium 4-styrenesulfonate) (PSS) using the spinning process. The adsorption process is governed by both the viscous force induced by fast solvent elimination and the electrostatic interaction between oppositely-charged species. On the other hand, the centrifugal and air shear forces applied by the spinning process enhance significantly the desorption of weakly-bound polyelectrolyte chains and also induce the planarization of the adsorbed polyelectrolyte layer. The surface of the multilayer films prepared with the spinning process is quite homogeneous and smooth. Also, a new approach to create multilayer ultrathin films with well-defined micropatterns in short process time is introduced. To achieve such micropatterns with high line resolution in organic multilayer films, microfluidic channels were combined with the convective self-assembly process employing both hydrogen bonding and electrostatic intermolecular interactions. As a next step, we extended the spin SA to the fabrication of multilayer micropatterns with vertical heterostructure. [ABSTRACT FROM AUTHOR]

The conventional radiologic method for liver segmentation is based on the position of the hepatic and portal veins. However, during surgery, liver segments are resected based on the distribution of hepatic portal blood flow. This discrepancy can lead to a number of problems, such as miscommunication among clinicians, missing the location of the segment with the hepatic mass, and the risk of extended hepatic resection. We suggest a novel method to determine hepatic segments based on portal blood flow, as in the surgical approach, but by using high and low mechanical indexes in contrast-enhanced ultrasonography with Sonazoid. This approach is helpful for preoperatively determining hepatic segments and reducing the risk of missing the location of a hepatic tumor or extended hepatic resection. [ABSTRACT FROM AUTHOR]

We introduce a general and versatile methodology that allows a facile incorporation of the functional components with completely different chemistry of hydrophilic/ hydrophobic properties within nanocomposite films, and furthermore combine a number of the distinctive advantages of traditional electrostatic layer-by-layer (LbL) assembly in aqueous media and covalent LbL assembly in nonpolar media. Our approach, amphiphilic LbL assembly, is based on the high affinity between sulfonic (or phosphonic) acid-functionalized materials in aqueous media and hydrophobic metal oxide (or metal) NPs stabilized by oleic acid (OA) in nonpolar solvent. For demonstrating the effectiveness of our approach, we show that amphiphilic LbL assembly can be easily applied to the preparation of functional colloid materials allowing the reversible phase transfer between aqueous and nonpolar media, and supercapacitor electrodes with high volumetric capacitance (280 F ⋅ cm-3 at 10 mV ⋅ s-1) using reduced graphene oxide with sulfonic acid moieties and well-defined OA-Fe3O4 NPs. [ABSTRACT FROM AUTHOR]

We introduce a novel and versatile approach for the preparation of multilayers, based on catalase-encapsulated gold nanoparticles (CAT-AuNP), allowing electrostatic charge reversal and structural transformation through pH adjustment. CAT-AuNP, which are synthesized directly from CAT stabilizer, can be electrostatically assembled with anionic and cationic PEs as a result of the charge reversal of the catalase stabilizers through pH control. In particular, at pH 5.2, near the pI of catalase, dispersed CAT-AuNP are structurally transformed into colloidal or network CAT-AuNP nanocomposites. Furthermore, we demonstrate that the layer-by-layer assembled multilayers composed of PEs and CAT-AuNP induce an effective electron transfer between CAT and the electrode as well as a high loading of CAT and AuNP, and resultantly exhibit a highly catalytic activity toward H2O2. [ABSTRACT FROM AUTHOR]

We demonstrate that TiOxnanocomposite films fabricated using electrostatic layer-by-layer (LbL) assembly improve the power conversion efficiency of photovoltaic cells compared to conventional TiOxfilms fabricated via the sol−gel process. For this study, titanium precursor/poly(allylamine hydrochloride) (PAH) multilayer films were first deposited onto indium tin oxide-coated glass to produce TiOxnanocomposites (TiOxNC). The specific effect of the LbL processed TiOxon photovoltaic performance was investigated using the planar bilayer TiOxNC and highly regioregular poly(3-hexylthiophene) (P3HT) solar cells, and the P3HT/LbL TiOxNC solar cells showed a dramatic increase in power efficiency, particularly in terms of the short current density and fill factor. The improved efficiency of this device is mainly due to the difference in the chemical composition of the LbL TiOxNC films, including the much higher Ti3ﴸ룺뚭 and the highly reactive facets of crystals as demonstrated by XPS and XRD measurement, thus enhancing the electron transfer between electron donors and acceptors. In addition, the grazing incidence wide-angle X-ray scattering (GIWAXS) study revealed the presence of more highly oriented P3HT stacks parallel to the substrate on the LbL TiOxNC film compared to those on the sol−gel TiOxfilms, possibly influencing the hole mobility of P3HT and the energy transfer near and at the interface between the P3HT and TiOxlayers. The results of this study demonstrate that this approach is a promising one for the design of hybrid solar cells with improved efficiency. [ABSTRACT FROM AUTHOR]

We describe a novel and versatile approach for preparing resistive switching memory devices based on transition metal oxides. A titania precursor and poly(allyamine hydrochloride) (PAH) layers were deposited alternately onto platinum (Pt)-coated silicon substrates using electrostatic interactions. The multilayers were then converted to TiO2nanocomposite (TiO2NC) films after thermal annealing. A top electrode was coated on the TiO2NC films to complete device fabrication. When an external bias was applied to the devices, a switching phenomenon independent of the voltage polarity (i.e., unipolar switching) was observed at low operating voltages (approximately 0.4 VRESETand 1.3 VSET), which is comparable to that observed in conventional devices fabricated by sputtering or metal organic chemical vapor deposition processes. The reported approach offers new opportunities for preparing inorganic material-based resistive switching memory devices with tailored electronic properties, allowing facile solution processing. [ABSTRACT FROM AUTHOR]

We describe a novel and versatile approach for preparing resistive switching memory devices based on binary transition metal oxides (TMOs). Titanium isopropoxide (TIPP) was spin-coated onto platinum (Pt)-coated silicon substrates using a sol−gel process. The sol−gel-derived layer was converted into a TiO2film by thermal annealing. A top electrode (Ag electrode) was then coated onto the TiO2films to complete device fabrication. When an external bias was applied to the devices, a switching phenomenon independent of the voltage polarity (i.e., unipolar switching) was observed at low operating voltages (about 0.6 VRESETand 1.4 VSET). In addition, it was confirmed that the electrical properties (i.e., retention time, cycling test and switching speed) of the sol−gel-derived devices were comparable to those of vacuum deposited devices. This approach can be extended to a variety of binary TMOs such as niobium oxides. The reported approach offers new opportunities for preparing the binary TMO-based resistive switching memory devices allowing a facile solution processing. [ABSTRACT FROM AUTHOR]