Extracting more light for vertical emission: high power continuous wave operation of 1.3-µm quantum-dot photonic-crystal surface-emitting laser based on a flat band.

For long distance optical interconnects, 1.3-µm surface-emitting lasers are key devices. However, the low output power of several milliwatts limits their application. In this study, by introducing a two-dimensional photonic-crystal and using InAs quantum dots as active materials, a continuous-wave, 13.3-mW output power, 1.3-µm wavelength, room-temperature surface-emitting laser is achieved. In addition, such a device can be operated at high temperatures of up to 90 °C. The enhanced output power results from the flat band structure of the photonic crystal and an extra feedback mechanism. Surface emission is realized by photonic crystal diffraction and thus the distributed Bragg reflector is eliminated. The proposed device provides a means to overcome the limitations of low-power 1.3-µm surface-emitting lasers and increase the number of applications thereof.

Quality Measurement and Improvement Study of Surgical Coronary Revascularization: Medication Adherence (MISSION-2).

BACKGROUND: Secondary preventive therapies play a key role in the prevention of adverse outcomes after coronary artery bypass grafting (CABG). However, medication adherence after CABG is often poor, and conventional interventions for improving adherence have limited success. With increasing penetration of smartphones, health-related smartphone applications might provide an opportunity to improve adherence. Carefully designed trials are needed to provide reliable evidence for the use of these applications in patients after CABG. METHODS: The Measurement and Improvement Studies of Surgical Coronary Revascularization: Medication Adherence (MISSION-2) study is a multicenter randomized controlled trial, aiming to randomize 1000 CABG patients to the intervention or control groups in a 1:1 ratio. We developed the multifaceted, patient-centered, smartphone-based Heart Health Application to encourage medication adherence in the intervention group through a health self-management program initiated during hospital admission for CABG. The application integrated daily scheduled reminders to take the discharge medications, cardiac educational materials, a dynamic dashboard to review cardiovascular risk factors and secondary prevention targets, and weekly questionnaires with interactive feedback. The primary outcome was secondary preventive medication adherence measured by the Chinese version of the 8-item Morisky Medication Adherence Scale at 6 months after randomization. Secondary outcomes included all-cause death, cardiovascular rehospitalization, and a composite of death, myocardial infarction, stroke, and repeat revascularization. DISCUSSION: Findings will not only provide evidence regarding the feasibility and effectiveness of the described intervention for improving adherence to CABG secondary preventive therapies but also explore a model for outpatient health self-management that could be translated to various chronic diseases and widely disseminated across resource-limited settings. TRIAL REGISTRATION: https://clinicaltrials.gov (NCT02432469).

Use of etanercept to treat rheumatoid arthritis in an HIV-positive patient: a case-based review.

Rheumatoid arthritis (RA) is a relatively common autoimmune disease that is associated with progressive disability and systemic complications, with a relatively high socioeconomic burden. The treatment of RA has been revolutionized by the use of biological drugs, such as anti-tumor necrosis factor (TNF) agents. A wide spectrum of RA disease severity has been reported among patients with human immunodeficiency virus (HIV) infection. Yet, only a few cases using anti-TNF therapy have been described in this clinical population. Therefore, the aim of our case-based review was to describe the successful use of etanercept in a 38-year-old female patient with RA concomitant with HIV infection, who had been resistant to the first-line anti-rheumatic therapies. As per routine care guidelines, the patient was screened for hepatitis virus infection, latent tuberculosis, and other infectious conditions, prior to the initiation of etanercept treatment. CD4 cell count, HIV viral load, and adverse effects were closely monitored during the treatment. The HIV infection remained stable with etanercept treatment, without the need for anti-retrovirus agents. No adverse effects and serious infections were identified during the treatment. Therefore, anti-TNF therapy is a viable alternative for the treatment of RA in patients with HIV, who do not respond to conventional anti-rheumatic therapies. The relationship between TNF-α and HIV infection, as well as cautionary guidelines regarding the utilization of anti-TNF therapy in this clinical population, is discussed.

Hybrid III-V/silicon laser with laterally coupled Bragg grating.

In this paper, we demonstrate a compact electrically pumped distributed-feedback hybrid III-V/silicon laser with laterally coupled Bragg grating for the first time to the best of our knowledge. The hybrid laser structure consists of AlGaInAs/InP multi-quantum-well gain layers on top of a laterally corrugated silicon waveguide patterned on a silicon on insulator (SOI) substrate. A pair of surface couplers is integrated at the two ends of the silicon waveguide for the optical coupling and characterization of the ouput light. Single wavelength emission of ~1.55µm with a side-mode-suppression- ratio larger than 20dB and low threshold current density of 1.54kA/cm(2) were achieved for the device under pulsed operation at 20 °C.

Chemical redox reactions induced by cryptoelectrons on a PMMA surface.

We show that pristine PMMA can spontaneously transfer electrons to species in a liquid, thereby inducing a variety of electron transfer reactions. The electrons that are transferred we call cryptoelectrons; these have a surface density of the order of 5 x 10(13) cm(-2) and are at a considerably more negative reduction potential than the PMMA bonding electrons. For example, metal ions including Ag(+), Cu(2+), and Pd(2+) were reduced and plated on a PMMA surface and Fe(CN)(6)(3-) was reduced to Fe(CN)(6)(4-). Moreover, protons were reduced when PMMA powder was dropped into a slightly acidic solution, resulting in a pH increase and hydrogen generation. Chemiluminescence was produced in a solution containing Ru(bpy)(3)(2+) and S(2)O(8)(2-) with the addition of PMMA powder. These results clearly demonstrate that there are available electrons in PMMA that can participate in redox reactions at a rather negative potential. We also show that contacting PMMA with Teflon depletes this electronic surface charge. However, the PMMA used for a redox reaction or contacted with Teflon that was depleted of the electronic surface charge could be recharged by contacting with a suitable reductant.

[Coexpression of hepatitis B virus X gene and hepatitis C virus C gene in HepG2 cells and its effect on the expression of VEGF].

OBJECTIVE: To establish an experimental model of HCV C-HBV X co-expression protein and explore its effect on the expression of VEGF. METHODS: The HBV X gene was recovered by enzyme excision and inserted into PBK-CMV and PBK-HCVC, and recombinant plasmids PBK-X and PBK-X-C were constructed. The plasmids PBK-CMV, PBK-X, PBK-HCVC and PBK-X-C were transfected into HepG2 cells with liposomes. After being selected by G418, resistant colonies were obtained. Reverse transcription PCR and Western blot were used to show HBV X and HCV core protein expression. VEGF was analyzed using immunohistochemical methods and Western blot. RESULTS: The recombinant plasmid PBK-X-C expressed HBV X and HCV core protein efficiently under the control of the vectors promoter. VEGF and VEGF mRNA of the cells co-expressing HCV C-HBV X proteins were higher than those cells expressing HBV X, HCV C and vector alone. CONCLUSION: HBV X-HCV C co-expression protein can increase the expression of VEGF of HepG2 cells. It suggests that HBV and HCV have a synergic action in the carcinogenesis.

[The role of mitochondrial damages in Helicobacter pylori-induced apoptosis of gastric cancer cells].

OBJECTIVE: To explain the role of mitochondrial pathway in the apoptosis of SGC-7901 cell line induced by concentrated Helicobacter pylori culture supernatant (CHCS). METHODS: Cytochrome oxidase (COX) I expression was detected by Western blotting. Cell apoptosis and mitochondrial membrane potential were measured by flow cytometry. RESULTS: CHCS could induce the apoptosis of SGC-7901 in a dose- and time-dependent manner. Apoptotic rates gradually enhanced followed by the concentrations increasing. The mitochondrial membrane potential (MMP) began to descend after treating CHCS for 4 h, and MMP descended most distinctly in 8 h. It descended the lowest point in 12 h, and it had no special changes in 24 h. The expression of COX I was notably lower than that of control group after CHCS treating (632.8 +/- 40.6 vs 895.1 +/- 44.2, P < 0.05). CONCLUSION: Mitochondrial pathway may play an important role in the apoptosis of SGC-7901 cells induced by CHCS.

Electrochemistry and electrogenerated chemiluminescence with a single faradaic electrode.

We describe an electrochemical cell containing a single faradic electrode (a Pt ultramicroelectrode) and a blocked (polarized) electrode (Si with an insulating SiO2 film) that served as a capacitive counter electrode. When a bias was applied between the two electrodes, a current was observed from a faradic process at Pt and a capacitive current at the blocking electrode. A steady charging current was obtained when the solution was moved along the insulator to continuously contact fresh surface (emersing a layer of charged ions and electronic countercharge into the gas phase). Electrogenerated chemiluminescence was clearly observed from a system containing Ru(bpy)(3)2+ in this kind of cell under pulsed excitiation, demonstrating that faradaic reactions can be carried out in an electrochemical cell without generation of any products at a counter electrode. The use of such a system for coulometric addition of desired species in nanosystems and in synthesis is suggested.

Pressure-induced insulator conductor transition in a photoconducting organic liquid-crystal film.

Intermolecular separation determines the extent of orbital overlap and thus the rate of electron transfer between neighbouring molecules in an organic crystal. If such a crystal is compressed, the resistivity decreases owing to a diminishing intermolecular distance. Metal insulator transitions have been observed by applying hydrostatic pressure to, for example, Langmuir films of metal nanoparticles. But previous attempts to observe a clear transition point in organic crystals, such as anthracene and tetracene, were not successful owing to difficulties with electrically insulating the high-pressure cell. Here we report a different approach by using a sample that is photoconductive and forms an organized film. A cylindrical tip (approximately 100 microm in diameter) was used to compress the sample instead of a piston/cylinder structure, entirely eliminating the problem of electrical insulation. Furthermore, by illuminating the sample with a laser, the conductivity of the sample is increased by several orders of magnitude. By monitoring the photocurrent with sensitivity at the 10(-13) A level, changes in resistivity at very low pressure could be monitored. We observe a sharp increase in current that could indicate a transition from hopping to delocalized conduction.

Individually addressable submicron scale light-emitting devices based on electroluminescence of solid Ru(bpy)3(ClO4)2 films.

A submicron light-emitting device (LED) was fabricated from lithographically fabricated parallel indium-tin oxide (ITO) finger electrodes (0.9 mum wide) separated by a 1.1 mum gap. A single layer of an amorphous (a) Ru(bpy)3(ClO4)2 film ( approximately 100 nm thick) was spin-coated on the electrode array. Ga:In or carbon paste was employed as a liftable upper contact electrode. Films ( approximately 1.5 mum thick) of single-crystal Ru(bpy)3(ClO4)2 (xyl) between two ITO electrodes in a sandwich cell were also prepared and produce electroluminescence. As with larger cells of this type, the high-resolution electroluminescence produced showed a high external efficiency ( approximately 3.4%), a low turn-on voltage (2.3 V), and reasonable stability. The single-crystal cells also behaved as photovoltaic devices and a short-circuit photocurrent was observed when they were irradiated without a bias voltage.