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The effects of the conventional isothermal bainitic transformation (CIT), two-step isothermal bainitic transformation (TIT) on the microstructure, mechanical behavior, and wear resistance of a medium-carbon low-Si steel were investigated. For the bainite reaction, it is well known that the bainite-plate size decreases as the transformation temperature is reduced. In comparison with the CIT, TIT produced finer bainitic ferrite plates with finer carbides, and an optimum combination of strength, ductility, and impact toughness (an ultimate tensile strength of 1500 MPa, total elongation of 8.6%, and V-notch impact value of 42 J), the wear rate is calculated to evaluate its wear performance, and the wear rates of a CIT sample and TIT sample were 0.36 × 10−4 and 1.46 × 10−4 mm3 N−1 m−1, respectively. [ABSTRACT FROM AUTHOR]

Braille system is widely used worldwide for communication by visually impaired people. However, there are still some visually impaired people who are unable to learn Braille system due to various factors, such as the age (too young or too old), brain damage, etc. A wearable and low-cost Braille recognition system may substantially help these people recognize Braille or assist them in Braille learning. In this work, we fabricated polydimethylsiloxane (PDMS)-based flexible pressure sensors to construct an electronic skin (E-skin) for the application of Braille recognition. The E-skin mimics human touch sensing function for collecting Braille information. Braille recognition is realized with a neural network based on memristors. We utilize a binary neural network algorithm with only two bias layers and three fully connected layers. Such neural network design remarkably reduces the calculation burden and, thus, the system cost. Experiments show that the system can achieve a recognition accuracy of up to 91.25%. This work demonstrates the possibility of realizing a wearable and low-cost Braille recognition system and a Braille learning-assistance system. [ABSTRACT FROM AUTHOR]

We demonstrate anti-misalignment acousto-optically (AO) Q-switched Ho: YLF ring cavity laser with a single corner cube prism (CCP) as the cavity mirror and a diode-pumped 1940 nm solid state laser as the pump source. We study the polarization state of oscillating light of ring cavity with the CCP by simulation calculations, which matched with the experimental results. In the continuous wave (CW) operation, the Ho: YLF laser achieves a total bidirectional output power of 3.8 W at the wavelength of 2063.5 nm, corresponding to an optical-to-optical conversion efficiency of 15% and a slope efficiency of 50.7%. The maximum allowable deviations of the CCP are 0.57° (pitch angle) and 1.65° (horizontal angle), respectively. We obtain a single pulse energy of 17 mJ and a pulse width of 113 ns at a pulse repetition frequency (PRF) of 100 Hz. The beam quality factors in the horizontal and vertical directions are M x 2 = 1.01 and M y 2 = 1.06, respectively, which are approached to the diffraction limit. [ABSTRACT FROM AUTHOR]

The first example of the sulfinylation of indoles with arylsulfinamides in water in the presence of trifluoroacetic acid as a promoter is described. The reaction occurs smoothly at room temperature under environmentally benign conditions without any catalyst, additive, ligand, or organic solvent. The developed sulfoxide synthetic protocol is attractive due to the use of water as the solvent and provides a novel and efficient route to a wide range of functionalized diaryl sulfoxides. [ABSTRACT FROM AUTHOR]

A novel fluorescent probe, 2-allyl-6-((2-((2-hydroxy-5-nitrobenzylidene)amino)ethyl)amino)-1H-benzo[de]isoquinoline- 1,3(2H)-dione (ABID), based on naphthalimide-Schiff base, has been designed and synthesized for the monitoring of Cu2+ ions. In solution (DMSO/HEPES, 1:1, v/v, pH 7.4), ABID displayed fluorescence quenching towards Cu2+ ions over other important metal ions. A good linearity with a correlation coefficient (R2) of 0.99 validated that the ABID probe could be used to detect Cu2+ ions in 0.5–5.0 μM concentrations. The limit of detection of ABID for Cu2+ could reach at 3.4 × 10–7 M level, and the quenching constant (KSV) of ABID towards Cu2+ was calculated to be 3.4 × 104 M–1. The 2:1 stoichiometry and the binding mode between ABID and Cu2+ were studied by a Job plot and UV-Vis and fluorescence titration. Additionally, ABID was successfully employed to monitor Cu2+ in the Yellow River and tap water samples. [ABSTRACT FROM AUTHOR]

Fe-6.5wt%Si soft magnetic powder cores were prepared by using an improved bluing insulation method. A high-quality oxide insulation layer with good temperature stability was found to distribute continuously in the intervals between the Fe-Si particles. The effects of the annealing temperature and the compaction pressure on the core’s magnetic properties were investigated in detail. It was found that high temperature and low compaction pressure are beneficial to decrease the core’s inner stress and high compaction pressure is helpful to reduce the air gap. All the variations of the magnetic performance for the powder cores discussed in this paper were explained reasonably by considering these two factors. From the point of view of low loss, 760 °C and 2090 MPa were confirmed to be the relatively best annealing temperature and compaction pressure, respectively. The μe, the % μe at 100 Oe, and the loss at 50 kHz/1000 Gs for the core prepared under these two conditions are 63.57, 72.82%, and 547.66 mW/cm3, respectively. [ABSTRACT FROM AUTHOR]

The PbPd1 − xNixO2 nanograin films with different Ni-doping levels (x = 0.037–0.150) were synthesized by the sol–gel spin-coating method and an oxidation treatment. The films with a thickness of about 210 nm were found to be single phase with a body-centered orthorhombic structure and to possess a large number of Pb vacancies. High-temperature ferromagnetism discovered in these films can be maintained above 380 K. Paramagnetism was also found in the films with high Ni-doping levels. The analysis on the XANES spectra and their first derivatives offered the evidences for the facts that the film’s ferromagnetism is intrinsic and the increase in the Pb valence from 2+ towards 4+, caused by the appearance of large amount of Pb vacancies and low electronegativity of Pb2+ ion, provides magnetic moments to the film’s magnetism. A carrier-mediated mechanism bridged to the bound magnetic polaron model based on the Pb vacancies, the doped Ni ions and the Pb ions with a valence higher than 2+ was adopted to interpret the origin of the magnetism within these PbPd1 − xNixO2 nanograin films. The variation of the specific area of the grain boundary was believed to have a great influence on the proportions of the film’s ferromagnetism and paramagnetism. [ABSTRACT FROM AUTHOR]

Natural rubber lamination is a kind of seismic isolation of bearings often used in civil engineering. The advantage of laminated bearings is large vertical stiffness and small lateral stiffness. In seismic regions, structural periods would be extended and the effect of seismic forces can be lowered using bearings. In previous tests, the static cyclic loading method was mainly used that failed to take account of the loading rate. The real-time substructure testing is proposed to simulate true seismic loads. This testing and test setup were first introduced, and the effect of the loading rate was studied. Then the effects of vertical pressure and peak acceleration of ground motion were studied. At last the test results were simulated by the finite element method, and an accurate method to calculate seismic responses of bridges with laminated bearings was proposed. [ABSTRACT FROM AUTHOR]

Background:Although exercise has been addressed as an adjuvant treatment for anxiety, depression and cancer-related symptoms, limited studies have evaluated the effectiveness of exercise in patients with lung cancer.Methods:We recruited 116 patients from a medical centre in northern Taiwan, and randomly assigned them to either a walking-exercise group (n=58) or a usual-care group (n=58). We conducted a 12-week exercise programme that comprised home-based, moderate-intensity walking for 40 min per day, 3 days per week, and weekly exercise counselling. The outcome measures included the Hospital Anxiety and Depression Scale and the Taiwanese version of the MD Anderson Symptom Inventory.Results:We analysed the effects of the exercise programme on anxiety, depression and cancer-related symptoms by using a generalised estimating equation method. The exercise group patients exhibited significant improvements in their anxiety levels over time (P=0.009 and 0.006 in the third and sixth months, respectively) and depression (P=0.00006 and 0.004 in the third and sixth months, respectively) than did the usual-care group patients.Conclusions:The home-based walking exercise programme is a feasible and effective intervention method for managing anxiety and depression in lung cancer survivors and can be considered as an essential component of lung cancer rehabilitation. [ABSTRACT FROM AUTHOR]

We integrated four gene expression profile data sets, namely two different pair-matched stage I lung adenocarcinoma data sets, secondary metastatic tumors vs benign tumors and lung tumor metastasizes to the brain, and we identified one kinase, T-LAK Cell-Originated Protein Kinase (TOPK), as a putative gene that promotes metastasis. To delineate the role of TOPK in lung cancer, we showed that overexpression of TOPK, but not a catalytically inactive form of TOPK, can enhance the migration and invasion of lung fibroblasts or cells with low TOPK expression. In addition, TOPK-induced cell migration was shown to be a PI3K/AKT-dependent event. TOPK concurrently promoted AKT phosphorylation at Ser473 and decreased the phosphatase and tensin homolog (PTEN) levels, whereas TOPK knockdown had the reverse effects. LY294002, a PI3K inhibitor, did not inhibit the TOPK-induced decrease in PTEN, and co-expression of PTEN significantly reduced TOPK-induced AKT phosphorylation in a dose-dependent manner; these results indicate that the TOPK-mediated PTEN decrease has an upstream role in regulating PI3K/AKT-stimulated migration. Using immunohistochemical analysis of lung cancer tissue samples, we showed that a high TOPK expression level correlates strongly with reduced overall and disease-free survivals. Moreover, an inverse correlation between TOPK and PTEN expression was present and is consistent with the biochemical findings. Finally, a combination of high TOPK and low PTEN expression was inversely correlated with overall and disease-free survivals, independent of other pathologic staging factors. Our results suggest that TOPK is a potential therapeutic target in lung cancer that promotes cell migration by modulating a PI3K/PTEN/AKT-dependent signaling pathway; they also suggest that high TOPK expression, either alone or in combination with a low level of PTEN, may serve as a prognostic marker for lung cancer. [ABSTRACT FROM AUTHOR]

The physical mechanisms leading to the efficiency droop of InGaN/GaN light-emitting diodes (LEDs) are theoretically investigated. We first discuss the effect of Auger recombination loss on efficiency droop by taking different Auger coefficients into account. It is found that the Auger recombination process plays a significant nonradiative part for carriers at typical LED operation currents when the Auger coefficient is on the order of 10−30 cm6 s−1. Furthermore, the InGaN/GaN multiple-quantum-well (MQW) LEDs with varied indium compositions in InGaN quantum wells are studied to analyze the wavelength-dependent efficiency droop. The simulation results show that the wavelength-dependent efficiency droop is caused by several different effects including non-uniform carrier distribution, electron overflow, built-in electrostatic field induced by spontaneous and piezoelectric polarization, and Auger recombination loss. These internal physical mechanisms are the critical factors resulting in the wavelength-dependent efficiency droop in InGaN/GaN MQW LEDs. [ABSTRACT FROM AUTHOR]

Terbium doped Y2O3 planar waveguides were fabricated by sol–gel process and dip-coating using yttrium acetate as precursor. Two different doping modes were compared, i.e. introduction in the sol of dispersed Tb3+ions from dissolved Tb(NO3)3, or of nanoparticles of Tb2O3 or [Y2O3:50% Tb] from an alcoholic suspension. The chemical and nanostructural properties were analyzed by infrared spectroscopy, transmission electron microscopy and X-ray diffraction. The Tb3+ fluorescence properties were studied as a function of temperature and atmosphere of the thermal treatments, and of the Tb3+ concentration. The fluorescence properties are discussed in relation to the quenching mechanisms induced by Tb4+ transformation, residual OH groups, and crystallites size and structure. Optical propagation losses of the Tb doped Y2O3 planar waveguides related to the doping modes and Tb3+ concentration are presented. Doping sol–gel films by nanoparticles is shown to be a valuable alternative to the conventional doping from dissolved terbium salt. [ABSTRACT FROM AUTHOR]

Children and adolescents living in earthquake impacted areas may present various post-traumatic responses and adjustment along the post-traumatic reconstructive phases. Their surrounding environmental damage and reconstructive conditions may influence their adjustment as well. As part of a prospective and longitudinal research project aims to investigate the range and severity of post-traumatic stress disorder (PTSD) symptoms in children and adolescents residing near the epicenter after the Taiwan 921 Earthquake, this paper reports the changes of PTSD symptoms over a 2-year period. The study also examines the effects of school damage and reconstructive condition on PTSD symptoms. Earthquake Exposure Index for Youths and Child Posttraumatic Stress Disorder Reaction Index were administered to 2,028 and 2,077 youths at the first and second year, respectively, from two heavily impacted townships. Given that location, gender, individual and dwelling trauma exposure dose effect were controlled through a balanced sampling procedure and prior statistical confirmation, post-traumatic phase and school damage condition yield significant main effects. Students from the heavily damaged schools consistently displayed significantly more PTSD symptoms, including re-experiencing/avoidance and numbness/maladaptive symptoms, than their counterparts at the first and second year. Decline of prevalence of PTSD symptoms was noted from the first year to the second. Accordingly, there may be a need to implement a broad disaster recovery project with periodic screenings as well as school-specific and school-based mental health program. [ABSTRACT FROM AUTHOR]

Single-crystalline InSb nanowire arrays were prepared by pulsed electrochemical deposition into anodic alumina membranes, and subjected to characterization using X-ray diffraction, field emission scanning electron microscope and transmission electron microscopy. A nonlinear I–V characteristic and a decreased resistance with temperature were observed in InSb nanowire arrays. The mechanisms of the different temperature dependencies of the resistance of InSb nanowires with different diameters were discussed. [ABSTRACT FROM AUTHOR]

The photoluminescence (PL) of anodic alumina membranes with different pore sizes is investigated in this paper. We observe that a small pore size leads to a decrease of photoluminescence intensity, an increase of the recombination lifetime, and a broadening of the emission band. The origin of the PL characteristics are discussed together with the decay measurement of the emission band. [ABSTRACT FROM AUTHOR]

Background: Incisional recurrence after thoracoscopic surgery has been reported infrequently. In recent years, several reports of port-site recurrence after laparoscopic oncologic procedures have been published. This study evaluates the incidence of incisional recurrence among patients with intrathoracic malignancy after diagnostic and therapeutic thoracoscopy.Methods: The medical records of all patients with intrathoracic malignancies who underwent thoracoscopic procedures between 1992 and 1998 at Chang Gung Memorial Hospital Linkou Medical Center were reviewed. Information includes preoperative tumor status, thoracoscopic findings, primary tumor location, tumor pathology, procedures performed, and perioperative complications were recorded.Results: A total of 1,069 patients with known intrathoracic malignancies underwent thoracoscopy. The mean follow-up time was 17.1 months (range, 1-68 months). Two recurrences at the incision were identified (0.19%). Both patients with incision-site recurrence had advanced intrathoracic disease at the time of thoracoscopy. The one patient had a malignant pleural effusion (T4), and the other had diffuse pleural metastasis.Conclusion: The incidence of incisional recurrence after thoracoscopic oncologic surgery is very low. When recurrence occurs at the incision, it is associated most commonly with advanced intrathoracic disease. Additional patients and a longer follow-up evaluation are required, however, to confirm this observation. [ABSTRACT FROM AUTHOR]

Background: Empyema frequently complicates the hospitalization of children; and in advanced stages, it often requires surgical intervention. In this study, we investigated the use of video-assisted thoracic surgery (VATS) for the management of postpneumonic empyema in children who have had an unsatisfactory medical response. Methods: We did a retrospective review of the medical records of 51 consecutive patients with loculated empyema (mean age, 5 years; range, 2 months to 15 years) hospitalized at Chang Gung Memorial Hospital between 1995 and 2000. All patients underwent debridement of the necrotic lung tissue and evacuation of the loculated empyema cavity using a VATS approach. Results: The mean operating time for the 51 patients was 90 min (range, 50–210); mean blood loss was 70 cc. Fever subsided within 72 h postoperatively in all patients. On average, chest tubing was removed on the 7th postoperative day (range, 4–18 days). However, in one patient who suffered from a prolonged air leak, the chest tube was not removed until day 18. The mean postoperative stay for all patients was 13.7 days (range, 9–23). No deaths occurred, and all of the children made a good recovery. A follow-up revealed that one of the 51 children patient suffered a left upper lung abscess 7 months after discharge. Left upper lobectomy was performed in this case, and the patient was discharged uneventfully 10 days after the operation. Conclusions: VATS is a safe and effective treatment for pediatric empyema. Thoracoscopic-assisted surgery facilitates visualization, evacuation, and debridement of the necrotizing lung tissue. Early surgical intervention can avoid lengthy hospitalization and prolonged intravenous antibiotic therapy, and it can accelerate clinical recovery. [ABSTRACT FROM AUTHOR]

Computed Tomography (CT) is a powerful method for non-destructive testing (NDT) and metrology awakes with expanding application fields. To improve the spatial resolution of high energy CT, a micro-spot gamma-ray source based on bremsstrahlung from a laser wakefield accelerator was developed. A high energy CT using the source was performed, which shows that the resolution of reconstruction can reach 100 μm at 10% contrast. Our proof-of-principle demonstration indicates that laser driven micro-spot gamma-ray sources provide a prospective way to increase the spatial resolution and toward to high energy micro CT. Due to the advantage in spatial resolution, laser based high energy CT represents a large potential for many NDT applications. [ABSTRACT FROM AUTHOR]