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Despite the need for molecularly smooth self-assembled monolayers (SAMs) on silicon dioxide surfaces (the most common dielectric surface), current techniques are limited to nonideal silane grafting. Here, we show unique bioinspired zwitterionic molecules forming a molecularly smooth and uniformly thin SAM in "water" in >1 min on various dielectric surfaces, which enables a dip-coating process that is essential for organic electronics to become reality. This monomolecular layer leads to high mobility of organic field-effect transistors (OFETs) based on various organic semiconductors and source/drain electrodes. A combination of experimental and computational techniques confirms strong adsorption (Wad < 20 mJ m-2), uniform thickness (∼0.5 or ∼1 nm) and orientation (all catechol head groups facing the oxide surface) of the "monomolecular" layers. This robust (strong adsorption), rapid, and green SAM represents a promising advancement toward the next generation of nanofabrication compared to the current nonuniform and inconsistent polysiloxane-based SAM involving toxic chemicals, long processing time (<10 h), or heat (<80 °C). [ABSTRACT FROM AUTHOR]

We report the controlled nanomorphology of semiconducting polymers on chemically and mechanically stable nanogrooved polymer substrates. By employing silicon dioxide thin films with finely adjusted thicknesses on nanogrooved polymer substrates, semiconducting polymer thin films oriented and aligned along the nanogrooves were obtained. Organic field-effect transistors (OFETs) fabricated from the oriented semiconducting polymer, poly[4-(4,4-dihexadecyl-4H-cyclopenta[1,2-b:5,4-b']dithiophen-2-yl)-alt-[1,2,5]thiadiazolo-[3,4-c]pyridine] (PCDTPT), yielded saturation hole mobilities as high as 19.3 cm² V-1 s-1, and the flexible "plastic" transistors demonstrated excellent mechanical stability under various bending conditions. These results represent important progress for solution-processed flexible OFETs and demonstrate that directed self-assembly of semiconducting polymers can be achieved by soft nanostructures. [ABSTRACT FROM AUTHOR]

We demonstrate efficient and air-stable small-molecule bulk heterojunction (SM BHJ) solar cells by introducing titanium suboxide (TiOx) between the active layer and the cathode as an electric adhesive layer. The SM BHJ solar cell with the TiOx interlayer exhibits improved power conversion efficiency of 6.4% as well as greatly enhanced device lifetime. Analysis of the dark diode characteristics and comparison of the current density-voltage characteristics upon heat annealing indicate that the TiOx interlayer improves the electrical contact between the active layer and the cathode, thereby resulting in efficient sweep-out of photogenerated charge carriers. [ABSTRACT FROM AUTHOR]

Study objectives: To determine whether inactive hepatitis B surface antigen (HBsAg) carriers are at a higher risk of drug-induced hepatotoxicity than control subjects during antituberculosis treatment with standard short-course regimens of isoniazid, rifampin, ethambutol, and/or pyrazinamide. Design: Retrospective case-control study. Setting: Tertiary university medical center. Patients: One hundred ten inactive HBsAg carriers with newly diagnosed active tuberculosis who had been treated with isoniazid, rifampin, ethambutol, and/or pyrazinamide were included in the study population. Inactive HBsAg carriers were defined as follows: (1) positive for HbsAg; (2) negative for hepatitis B e antigen (HBeAg), positive for antibody to HBeAg; (3) < 105 copies per mL of serum hepatitis B virus DNA; and (4) normal pretreatment aspartate aminotransferase (AST)/alanine aminotransferase (ALT) levels. Ninety-seven HBsAg-negative patients who received standard antituberculosis medication were selected as control subjects. Results: The baseline characteristics of the 110 inactive HBsAg carriers were similar to those of the 97 noncarriers. A total of 85% of persons in both groups had received an initial treatment regimen that included pyrazinamide. Thirty-eight inactive HBsAg carriers (35%) and 19 control subjects (20%) exhibited elevated liver enzyme levels during antituberculosis treatment (p = 0.016). Drug-induced hepatotoxicity, which was defined as a liver transaminase level of > 120 IU/L, occurred more frequently in HBsAg carriers (9 of 110 carriers; 8%) than in control subjects (4 of 97 control subjects; 4%), although this was not a statistically significant discrepancy (p = 0.230). More importantly, HBsAg carriers (n = 9; 8%) who received antituberculosis therapy evidenced a higher proportion of moderate-to-severe drug-induced hepatotoxicity when compared with the control subjects (n = 2; 2%; p = 0.05). Isoniazid and rifampin were reintroduced as therapy after AST/ALT levels returned to baseline values in 10 patients (6 HBsAg carriers and 4 control subjects) among the 13 patients exhibiting drug-induced hepatotoxicity, and these retrials proved to be successful in 7 patients (5 HBsAg carriers and 2 control subjects). Conclusions: Tuberculosis treatment in HBsAg-positive and HBeAg-negative inactive carriers could be pursued in the usual manner, using standard short-course regimens of isoniazid, rifampin, ethambutol, and/or pyrazinamide, with the condition that monthly liver function tests are performed. [ABSTRACT FROM AUTHOR]

The most common cardiac cause of massive hemoptysis is mitral stenosis. Mitral regurgitation is rarely complicated by massive hemoptysis. A 48-year-old man with no significant medical history was admitted to our hospital with hemoptysis and production of 500 mL of blood within 24 hours. A pan-systolic murmur was found on chest examination. A chest computed tomography showed airspace consolidation in the right upper and middle lobes, with faint bilateral ground glass opacity. Echocardiography revealed mitral valve prolapse and grade IV mitral regurgitation. The patient was diagnosed with sporadic primary mitral valve prolapse. After mitral valve repair surgery, the patient recovered fully. [ABSTRACT FROM AUTHOR]

Vellus hair cysts typically appear as numerous small papules in the precordial area in children. Treatment is generally not necessary as most cases resolve spontaneously. We report a case of a vellus hair cyst that was unique in that it manifested as a solitary mass in the postauricular area and it had persisted for 16 years. The tumor was surgically excised. We also review the literature on this condition. [ABSTRACT FROM AUTHOR]