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Purpose The study aimed to investigate the current status and prognostic factors for overall survival in patients who had undergone pulmonary metastasectomy for colorectal cancer. Materials and Methods The data of 2,573 patients who had undergone pulmonary metastasectomy after surgery for colorectal cancer between January 2009 and December 2014 were extracted from the Korean National Health Insurance Service claims database. Patient-, colorectal cancer-, pulmonary metastasis-, and hospital-related factors were analyzed using the Kaplan-Meier method, log-rank test, and Cox proportional hazards analysis to identify prognostic factors for overall survival after pulmonary metastasectomy. Results The mean age of the patients was 60.9±10.5 years; 66.2% and 79.1% of the participants were male and had distally located colorectal cancer, respectively. Wedge resection (71.7%) was the most frequent extent of pulmonary resection; 21.8% of the patients underwent repeated pulmonary metastasectomies; 73% of pulmonary metastasectomy cases were performed in tertiary hospitals; 53.9% of patients were treated in Seoul area; 82% of patients received chemotherapy in conjunction with pulmonary metastasectomy. The median survival duration was 51.8 months. The 3- and 5-year overall survival rates were 67.7% and 39.4%, respectively. In multivariate analysis, female sex, distally located colorectal cancer, pulmonary metastasectomy-only treatment, and high hospital volume (> 10 pulmonary metastasectomy cases/yr) were positive prognostic factors for survival. Conclusion Pulmonary metastasectomy seemed to provide long-term survival of patients with colorectal cancer. The female sex, presence of distally located colorectal cancer, and performance of pulmonary metastasectomy in high-volume centers were positive prognostic factors for survival. [ABSTRACT FROM AUTHOR]

Molybdenum diselenide (MoSe2) has attracted attention as a potential semiconductor platform. However, the as-synthesized MoSe2 field-effect transistors (FETs) tend to exhibit the arbitrary properties of n-type, p-type, or ambipolar behavior due to the uncontrolled growth condition. Here, two-step functionalization is proposed to achieve n-doping effect and long-term stability in chemical vapor deposition (CVD)-grown MoSe2 FETs using oxygen plasma treatment followed by the deposition of an Al2O3 layer. After the two-step surface functionalization procedure, three types of multilayer MoSe2 FETs are all converted to n-type with the improvement of their electrical characteristics and stability; the n-doped multilayer MoSe2 FETs exhibit an enhancement in field-effect mobility from 12.23 to 31.57 cm2 V-1 s-1 and a 3 times higher Ion/Ioff, compared to pristine multilayer MoSe2 FETs. This enhancement of electric performance is attributed to the oxidation of topmost MoSe2 to interfacial MoOx with SeOx induced by the oxygen plasma treatment, as well as to the existence of fixed positive charges in deposited Al2O3. The functionalized devices exhibit excellent stability against stress, as confirmed with negative bias illumination stress tests for 7200 s. Moreover, an environmental stability test for 21 days reveals no degradation in electric performance of MoSe2 FETs. [ABSTRACT FROM AUTHOR]

Various strategies and mechanisms have been suggested for investigating a Schottky contact behavior in molybdenum disulfide (MoS2) thin-film transistor (TFT), which are still in much debate and controversy. As one of promising breakthrough for transparent electronics with a high device performance, we have realized MoS2 TFTs with source/drain electrodes consisting of transparent bi-layers of a conducting oxide over a thin film of low work function metal. Intercalation of a low work function metal layer, such as aluminum, between MoS2 and transparent source/drain electrodes makes it possible to optimize the Schottky contact characteristics, resulting in about 24-fold and 3 orders of magnitude enhancement of the field-effect mobility and on-off current ratio, respectively, as well as transmittance of 87.4 % in the visible wavelength range. [ABSTRACT FROM AUTHOR]

Conventional α-Si:H phototransistors exhibit poor photosensitivity due to low photo-conversion efficiency. To overcome this intrinsic limit, we introduce gate underlap inα -Si:H phototransistors and demonstrate photosensitivity enhancement. We show that photocurrent can be significantly larger than dark current by 4 orders of magnitude, using 1-μm gate underlap at incident optical power density (Pinc) of 3.2 W/cm2. Our 1-μm gate-underlap phototransistor exhibits higher photosensitivity than the device without gate underlap by 64 times with Pinc=0.2 W/cm2 and a wavelength of 785 nm. Our gate-underlapped phototransistors also show excellent time-resolved photoswitching behaviors, demonstrating the great potential for highly sensitive photodetectors [ABSTRACT FROM AUTHOR]

Objective. This study is a pilot study to assess the clinical outcomes of percutaneous disc decompression using the L'DISQ in patients with lumbar discogenic pain. Study Design. An institutional, prospective clinical data analysis. Methods. We ablated the torn annulus using L'DISQ on 20 patients with axial low back pain for at least 3 months (average 29 months) unresponsive to conservative management. Before the therapeutic procedure, all the patients had been diagnosed with lumbar discogenic pain through provocation discography, which had confirmed the level of painful discs. The torn annulus was identified through lumbosacral magnetic resonance image and computed tomographic discogram. Baseline data were prospectively gathered before the procedure and at 1, 4, 12, 24, and 48 weeks post-procedure. Data included pain intensity (visual analog scale [VAS]), measure of disability (Oswestry Disability Index [ODI] and Rolando-Morris Disability Questionnaire [RM]), and health-related quality of life (Bodily Pain Scale of Short Form-36 version 2 [SF-36 BP]). Results. At 48 weeks, the VAS fell from 7.55 ± 1.28 to 3.60 ± 2.28 scores, the ODI and RM had decreased significantly, and the SF-36 BP showed significant improvement (P < 0.05). The success rates of procedure were 55.0% at 48 weeks. There were no complications with the exception of a minor venous bleeding at the site of needle puncture. Conclusions. The L'DISQ device is specifically designed to ablate adjacent disc tissue using a wand that can be navigated into a torn annulus. Following ablation, we measured clinically significant pain improvement and decreased disability for patients with axial low back pain. [ABSTRACT FROM AUTHOR]

We report on the fabrication and nanoscale luminescence characteristics of an isolated rubrene single nanoparticle (NP). A solvent-vapor annealing process changed pristine rubrene NPs, prepared by a reprecipitation method, to perfect crystalline NPs. The formation and structural properties of crystalline and non-crystalline rubrene NPs were studied through SEM, HR-TEM, and X-ray diffraction experiments. The nanoscale photoluminescence (PL) characteristics and the luminescence color of the rubrene single NP were measured using a high-resolution laser confocal microscope with color charge-coupled device images. In comparison with the pristine rubrene NPs, the crystalline NPs exhibited highly bright and sharp light emission. The main PL peak at 561–562 nm for the crystalline rubrene single NP had a relatively narrow line-width and became more dominant through a solvent-vapor annealing. The enhanced and sharp light emission of the crystalline rubrene single NP originated from the strong π–π interaction of rubrene molecules along the major crystalline axis in the nano-sized structure. [ABSTRACT FROM AUTHOR]

An institutional, prospective clinical data analysis. To evaluate the safety and efficacy of a new navigable percutaneous disc decompression device (L'DISQ) in patients with lumbar disc herniation with radicular pain. We performed disc decompressions using L'DISQ on 27 patients with persistent disabling back and leg pain for 1 month or longer (average 6.48 months) due to a herniated lumbar intervertebral disc. Baseline data were prospectively gathered before the index procedure and at 1, 4, 12, and 24 weeks post-procedure. Data included pain intensity (visual analog scale [VAS]), measure of disability (Oswestry Disability Index [ODI] and Rolando-Morris Questionnaire [RM]), health-related quality of life (Bodily Pain Scale of Short Form-36 version 2 [SF-36 BP]), and passive straight leg raising test (SLR). The VAS fell from 7.08 ± 1.22 to 1.84 ± 0.99 scores at 24 weeks post-procedure. At 24 weeks, the ODI had fallen from 41.88 ± 10.61 to 16.66 ± 8.55% and the RM from 11.52 ± 3.91 to 2.68 ± 1.97 points. The SF-36 BP dropped significant improvement from 32.89 ± 5.83 to 49.57 ± 4.96 scales. In the SLR test, the angular change of 24 weeks showed considerable improvement from 60.20 ± 20.02 to 83.00 ± 14.29 degrees. No major complication occurred, although two cases developed a disc reherniation 1 month post-procedure. The L'DISQ device is specifically designed to remove herniated disc using a wand that can be navigated into a disc protrusion or extrusion. Following decompression, we measured clinically significant pain improvement and decreased disability for patients with both radicular and axial pain caused by protruded and extruded discs. [ABSTRACT FROM AUTHOR]

Background: Recent developments in minimally invasive surgery have introduced scarless surgeries such as natural orifice transluminal endoscopic surgery (NOTES) and single-site laparoscopic surgery. Among surgical procedures, the appendectomy is one of those targeted for early adoption of new minimally invasive surgical techniques. To date, however, only a limited number of case series have been reported. Thus, the current study aimed to evaluate the safety and feasibility of single-site laparoscopic appendectomy (SSLA) compared with conventional laparoscopic appendectomy (CLA). Methods: The study enrolled 43 patients who consecutively received laparoscopic appendectomy and divided them into SSLA and CLA groups. The clinical characteristics and short-term operative outcomes of these patients were reviewed and compared. Results: The 23 patients receiving SSLA did not differ from the 20 patients receiving CLA in terms of clinical characteristics including gender, age, body mass index (BMI), location of appendix, and severity of inflammation. Likewise, operation times and postoperative complication rates did not differ between the two groups. Short-term operative outcomes such as visual analog pain score and hospital stay were not different. The incision was shorter for SSLA (22.9 ± 3.9 mm) than for CLA (29.0 ± 3.0 mm) ( p < 0.001). Conclusions: The results of the current study suggest that SSLA is a feasible surgical alternative to CLA with an equivalent level of safety. The data also suggest that SSLA results in better cosmetic outcomes than CLA. Data from larger research studies are necessary to confirm these results and validate the use of SSLA over CLA. [ABSTRACT FROM AUTHOR]

A model for the dynamic response of microelectromechanical-systems micromirrors with angular vertical combdrive electrostatic actuators has been proposed based on a numerical solution of the nonlinear dynamic equations for torsional oscillation. The torque generated by the electrostatic drive is assumed to depend at least on the second order of the turn angle, and the model shows a shift in the resonant frequency with drive voltage, in agreement with the experimental results obtained from components fabricated by self-assembly of bonded silicon parts. The dynamic response of a corner cube reflector (CCR) based on a pair of scanning mirrors and a fixed mirror is predicted using the model, and the theoretical response agrees well with the experimental results. From the model, a small initial misalignment of the CCR mirrors can be determined [ABSTRACT FROM PUBLISHER]

Intrinsically conducting polymer (ICP)/textile composites were prepared by coating polypyrrole (PPy) or poly (3,4-ethylenedioxythiopene) (PEDOT) on the fabrics through chemical and electrochemical oxidation of pyrrole or EDOT. We investigated the effects of the preparation conditions on the properties of the resulting composite such as ICP content, electrical conductivity, surface morphology, and electromagnetic interference shielding effectiveness (EMI SE). The specific volume resistivity of the composite was as low as 0.3 Ω-cm, giving rise to about 36 dB of EMI SE over the wide range of frequency up to 1.5 GHz. We also prepared the elastic textile composites, exhibiting a monotonic increase of the electrical resistance with the elongation up to 50%. We, therefore, propose the elastic textile composite can be used as a strain sensor for large deformation. [ABSTRACT FROM AUTHOR]

PET fabric/polypyrrole composites with high electrical conductivity were prepared by polymerization of polypyrrole on a PET fabric through both chemical and electrochemical oxidation of pyrrole monomer. We investigated environmental stability of the composite and measured activation energy using the Arrhenius Equation. [ABSTRACT FROM AUTHOR]

Conducting polypyrrole (PPy) nanowires (NWs) were irradiated by a relatively high energy (300 keV–2 MeV) electron-beam (e-beam) generated from a linear electron accelerator in an atmospheric environment. From the current-voltage characteristics of pristine and 2 MeV e-beam irradiated PPy NWs, we observed a dramatic variation in resistance from 8.0×102 to 1.45×108 Ω, that is, we observed a transition from conducting states to nonconducting states through the e-beam irradiation. To discern conformational changes and the doping states of PPy NWs through the e-beam irradiation, we measured Raman and ultraviolet-visible absorption spectra for the PPy NWs. As the energy of the e-beam irradiation increased, we observed that the PPy NWs were changed from doping states to dedoping states with conformational modification including the variation in π-conjugation length. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) layered semiconductors are emerging as promising candidates for next-generation thin-film electronics because of their high mobility, relatively large bandgap, low-power switching, and the availability of large-area growth methods. Thin-film transistors (TFTs) based on multilayer transition metal dichalcogenides or black phosphorus offer unique opportunities for next-generation electronic and optoelectronic devices. Here, we review recent progress in high-mobility transistors based on multilayer 2D semiconductors. We describe the theoretical background on characterizing methods of TFT performance and material properties, followed by their applications in flexible, transparent, and optoelectronic devices. Finally, we highlight some of the methods used in metal-semiconductor contacts, hybrid structures, heterostructures, and chemical doping to improve device performance. [ABSTRACT FROM AUTHOR]

We report on optically transparent thin film transistors (TFTs) fabricated using multilayered molybdenum disulfide (MoS2) as the active channel, indium tin oxide (ITO) for the back-gated electrode and indium zinc oxide (IZO) for the source/drain electrodes, respectively, which showed more than 81% transmittance in the visible wavelength. In spite of a relatively large Schottky barrier between MoS2 and IZO, the n-type behavior with a field-effect mobility (μeff) of 1.4 cm2 V−1 s−1 was observed in as-fabricated transparent MoS2 TFT. In order to enhance the performances of transparent MoS2 TFTs, a picosecond pulsed laser was selectively irradiated onto the contact region of the IZO electrodes. Following laser annealing, μeff increased to 4.5 cm2 V−1 s−1, and the on-off current ratio (Ion/Ioff) increased to 104, which were attributed to the reduction of the contact resistance between MoS2 and IZO. [ABSTRACT FROM AUTHOR]