Molecular Engineering of Printed Semiconducting Blends to Develop Organic Integrated Circuits: Crystallization, Charge Transport, and Device Application Analyses.

Solution-based printing has contributed to the facile deposition of various types of materials, including the building blocks of printed electronics. In particular, solution-processable organic semiconductors (OSCs) are regarded as one of the most fascinating candidates for the fabrication of printed electronics. Herein, we report electrohydrodynamic (EHD) jet-printed p- and n-type OSCs, namely 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-PEN) and 6,13-bis((triisopropylsilyl)ethynyl)-5,7,12,14-tetraazapentacene (TIPS-TAP), and their use as single-OSC layers and as OSC mixed p-n layers to fabricate solution-processed p-, n-, and ambipolar-type organic field-effect transistors (OFETs). Use of the dragging mode of EHD jet printing, a process driven under a low electrostatic field with a short nozzle-to-substrate distance, was found to provide favorable conditions for growth of TIPS-PEN and TIPS-TAP crystals. In this way, the similar molecular structures of TIPS-PEN and TIPS-TAP yielded a homogeneous solid solution and showed ambipolar transport properties in OFETs. Therefore, the combination of single- and mixed-OSC layers enabled the preparation of various charge-transported devices from unit to integrated devices (NOT, NAND, NOR, and multivalued logic). Therefore, this fabrication technology can be useful for assisting in the production of OSC layers for practical applications in the near future.

Mechanical and biological behavior of ultrafine-grained Ti alloy aneurysm clip processed using high-pressure torsion.

Severe plastic deformation (SPD) has recently been advanced as the main process for fabricating bulk ultrafine grained or nanocrystalline metallic materials, which present much higher strength and better bio-compatibility than coarse-grained counterparts. Medical devices, such as aneurysm clips and dental implants, require high mechanical and biological performance (e.g., stiffness, yield strength, fatigue resistance, and bio-compatibility). These requirements match well the characteristics of SPD-processed materials. Typical aneurysm clips are made of a commercial Ti-6Al-4V alloy, which has higher yield strength than Ti. In this work, Ti and Ti-6Al-4V workpieces were processed by high-pressure torsion (HPT) to enhance their mechanical properties. Tensile tests and hardness tests were performed to evaluate their mechanical properties, and their microstructure was investigated. The hardness and yield stress of the HPT-processed Ti are comparable to those of the initial Ti-6Al-4V due to significantly refined microstructure. Finite element analyses for evaluating the opening performance of a specific geometry of the YASARGIL aneurysm clip were carried out using mechanical properties of the initial and HPT-processed Ti and Ti-6Al-4V. These results indicate that SPD-processed Ti could be a good candidate to substitute for Ti-6Al-4V in aneurysm clips.

Modeling studies on the uptake of hydrogen molecules by graphene.

Detailed ab initio molecular orbital calculations on the interactions of molecular hydrogen, H2, with various poly-aromatic hydrocarbons (PAHs) as a model system for graphene were carried out to accurately describe the physisorption phenomenon. The binding energies corrected for the basis set superposition error, ΔEbind(BSSE), were obtained using the optimized geometries at the MP2 level with a large basis set and were compared with the single point binding energies, denoted as ΔEbind(BSSE-s), using large basis sets on the geometries optimized at the small basis sets, such as SVP and TZVP. The calculations showed that the ΔEbind(BSSE-s) values were similar to those at the MP2 level with the large basis sets. The binding strength increased gradually with increasing size of the PAHs. The ΔEbind(BSSE-s) for an infinite graphene sheet was estimated to be -1.70 kcal mol(-1) using the non-linear curve fitting method. The present work could be expected to provide more useful and reliable information on H2 physisorption.

Fingertip reconstruction with simultaneous flaps and nail bed grafts following amputation.

PURPOSE: To report our technique and results with treating fingertip amputations with flaps and simultaneous nailbed grafts. METHODS: We reconstructed 20 fingertip amputations with loss of bone and nail with flaps combined with nailbed grafts. We reconstructed the volar side of the fingertip with a flap, and the dorsal side of the fingertip with a nailbed grafted to the raw inner surface of the flap. We employed volar V-Y advancement flaps for transverse or dorsal oblique fingertip injuries and generally used abdominal flaps for volar oblique fingertip injuries. We harvested nailbeds from the amputated finger or from the patient's first toe. RESULTS: The length of the amputated fingertips was restored with the flaps, and the lost nailbeds were restored to their natural appearance with the nailbed grafts. We classified the results according to the length of the reconstructed fingertip and the appearance of the nail. Excellent or good results were achieved in 16 cases. Three cases had fair results and 1 had a poor result. We observed favorable results for distal fingertip amputations (Allen type II or III). In particular, most cases that were reconstructed with volar V-Y advancement flaps combined with nailbed grafts demonstrated favorable results. CONCLUSIONS: This method is useful for the restoration of dorsal oblique or transverse type fingertip amputations and is a good alternative when replantation is not an option.

Comprehensive studies on the tautomerization of glycine: a theoretical study.

The tautomerization process of glycine between the neutral (NE) and zwitterionic (ZW) forms in aqueous solution was explored theoretically using the conductor-like polarizable continuum model (CPCM) by adopting the PAULING cavity model at the B3LYP, MP2 and CCSD levels with the 6-311+G(d,p) basis set. The tautomerization of glycine is unable to be predicted satisfactorily within the equilibrated framework of the CPCM method. Instead, in this study, three plausible non-equilibrated solvation situations were assumed: (S-1) one water molecule attached to the transferring proton in the ZW moves together with the transferring proton; (S-2) one water molecule attached to the transferring proton in the ZW remains motionless at a fixed position near the NH(2) fragment at the TS structure; and (S-3) proton transfer occurs without changing the position of the surrounding water molecules from their initial state, the ZW form, in the eight water clusters. Although the calculation of (S-3) failed, the Gibbs free energies of activation for tautomerization from the ZW to NE, ΔG(≠)(ZW → NE), was well consistent with the experimental findings in the hypothetical non-equilibrated solvation states of (S-1) and (S-2). This suggests that non-equilibrium solvation is essential to explain the observed experimental data.

Sodium iodide symporter and phosphatase and tensin homolog deleted on chromosome ten expression in cholangiocarcinoma analysis with clinicopathological parameters.

BACKGROUND/AIMS: This study was performed to investigate the correlation of sodium iodide symporter (NIS) expression with the functionality and loss of phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression in human cholangiocarcinoma (CCA). METHODS: Immunohistochemistry for the expression of NIS and PTEN was performed in 60 biopsy specimens of CCA. The clinicopathological parameters were retrospectively identified from medical records. The expression pattern of NIS and loss of PTEN expression were analyzed in association with the clinicopathological characteristics, including survival. RESULTS: Normal biliary trees displayed NIS expression, but hepatocytes did not. NIS expression was divided into two patterns: cytoplasmic and membranous. Fifty-nine cases, all except for one case, displayed NIS expression in tumor cells. Twenty-two cases (33.3%) were mixed pattern, and 39 cases (65.05%) were cytoplasmic pattern; the pure membranous pattern was not noted. There was no association between the NIS expression pattern and clinicopathological parameters, including age, sex, differentiation grade, T stage and tumor, node, metastasis stage (p>0.05). The survival rates were similar among various NIS expression patterns. Normal hepatocytes and biliary trees exhibited PTEN expression in the nucleus and cytoplasm. CCA cells displayed nuclear staining. Thirty-six (60.0%) of 60 cases displayed a loss of PTEN expression. The loss of PTEN expression was observed in the advanced T-stage group (p=0.0036), but there was no association between the loss of PTEN expression and other clinicopathological parameters (p>0.05). No association between the loss of PTEN expression and survival was noted. CONCLUSIONS: NIS is expressed in most types of human CCA. The expression pattern suggests a role in cancer development. PTEN loss expression is common in the context of human CCA, especially in the advanced T stage.

Total synthesis of chiricanine A, arahypin-1, trans-arachidin-2, trans-arachidin-3, and arahypin-5 from peanut seeds.

The first and efficient syntheses of the naturally occurring prenylated stilbenes chiricanine A (2), arahypin-1 (3), trans-arachidin-2 (4), trans-arachidin-3 (5), and arahypin-5 (6) are described. Syntheses of 2 and 3 were accomplished by either a convergent sequence or a one-step reaction starting from pinosylvin. Syntheses of 4, 5, and 6 were achieved from (E)-3,5-bis-methoxymethyl-4'-triisopropylsilyloxystilbene obtained by a Horner-Wadsworth-Emmons reaction between a benzaldehyde possessing bis-methoxymethyl ether groups and a benzyl phosphonate with a triisopropylsilyloxy group.

Hepatopulmonary syndrome induced by common bile duct ligation in a rabbit model: correlation between pulmonary vascular dilatation on thin-section CT and angiography and serum nitrite concentration or endothelial nitric oxide synthase (eNOS)1 expression.

OBJECTIVE: To investigate the correlation between radiologic vascular dilatation and serum nitrite concentration and eNOS expression in the endothelial cell and pneumocyte in a rabbit model of hepatopulmonary syndrome induced by common bile duct ligation (CBDL). MATERIALS AND METHODS: Thin-section CT scans of the lung and pulmonary angiography were obtained 3 weeks after CBDL (n = 6), or a sham operation (n = 4), and intrapulmonary vasodilatation was assessed. The diameter and tortuosity of peripheral vessels in the right lower lobe by thin-section CT and angiography at the same level of the right lower lobe in all subjects were correlated to serum nitrite concentration and eNOS (endothelial nitric oxide synthase) expression as determined by immunostaining. RESULTS: The diameters of pulmonary vessels on thin-section CT were well correlated with nitrite concentrations in serum (r = 0.92, p < 0.001). Dilated pulmonary vessels were significantly correlated with an increased eNOS expression (r = 0.94, p < 0.0001), and the severity of pulmonary vessel tortuosity was found to be well correlated with serum nitrite concentration (r = 0.90, p < 0.001). CONCLUSION: The peripheral pulmonary vasculature in hepatopulmonary syndrome induced by CBLD was dilated on thin-section CT and on angiographs. Our findings suggest that peripheral pulmonary vascular dilatations are correlated with serum nitrite concentrations and pulmonary eNOS expression.

Ultrasonographic evidence of phenotypic instability during hepatocarcinogenesis in N-nitrosomorpholine-treated rats.

Carcinogen-induced hepatoma in immunocompetent animal models has shown a progress similar to the clinical course of human hepatoma. Ultrasonography (US) was used for consecutive evaluation of the phenotypic changes in Sprague-Dawley rats exposed for 8 weeks to N-nitrosomorpholine (NNM, 200 mg/L). Three distinctive US findings were ascites, coarseness (defined as small and heterogeneously widespread increased echogenecity), and nodularity (defined as a >0.6-cm-sized echogenic region and clearly showing a tumor-like mass). Abdominal ascites was observed in 5 of 26 rats at week 8 NNM posttreatment and the number of rats showing ascites gradually increased. Coarseness (22 of 26 rats) and nodularity (1 of 18) appeared at weeks 8 and 17 NNM posttreatment, respectively. The gross and histological findings indicated that coarseness and nodularity shown in US reflected fibrosis and hepatocellular carcinoma or cholangiofibroma, respectively. The computer-aided quantification of coarseness and nodularity showed that the regression-linked phenotypic instability was present in coarseness but not in nodularity. We conclude that the heterogeneity of preneoplasia in NNM-treated rats might be induced by phenotypic instability rather than random initiating events of preneoplastic lesion.