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Optical confinement effects are investigated in InGaN/GaN axial-heterostructure nanolasers. Cylindrical nanorods with GaN/InGaN/GaN structures are prepared using combined processes of top-down and bottom-up approaches. The lasing of InGaN is observed at a low threshold (1 μJ cm-2), which is attributed to an efficient carrier transfer process from GaN to InGaN. The lasing of GaN is also found in the threshold range of 10-20 μJ cm-2 with a superlinear increase in emission intensity and high quality factors (Q = 1000), implying that dual wavelengths of lasing are tunable as a function of excitation intensity. The non-classical Fabry-Pérot modes suggest strong light-matter interactions in nanorods by optical confinement effects. The polarization of lasing indicates that the non-classical modes are in the identical transverse mode, which supports the formation of exciton-polaritons in nanorods. Polariton lasing in a single axial-heterostructure nanorod is observed for the first time, which proposes small-sized light sources with low threshold, polarized light, and tunable wavelengths in a single nanorod.

Significance Septic shock commonly leads to multiorgan injury both directly via tissue inflammation and secondarily via hypoperfusion, but both can result in mitochondrial N-formyl peptide (mtFP) release into the circulation. However, no studies have evaluated the role of circulating mtFPs during septic shock. We found that a relatively high plasma nicotinamide adenine dinucleotide dehydrogenase subunit-6 (the most potent human mtFP) level was independently associated with the development of secondary infection in patients with septic shock and that the increased susceptibility to secondary infection is partly attributed to the suppression of polymorphonuclear leukocyte (PMN) chemotaxis by mtFP occupancy of formyl peptide receptor-1. Incorporation of these findings into therapeutic strategies may improve clinical outcomes in septic shock patients by preventing PMN chemotactic anergy., Secondary infections typically worsen outcomes of patients recovering from septic shock. Neutrophil [polymorphonuclear leukocytes (PMNs)] migration to secondarily inoculated sites may play a key role in inhibiting progression from local bacterial inoculation to secondary infection. Mitochondrial N-formyl peptide (mtFP) occupancy of formyl peptide receptor-1 (FPR1) has been shown to suppress PMN chemotaxis. Therefore, we studied the association between circulating mtFPs and the development of secondary infection in patients with septic shock. We collected clinical data and plasma samples from patients with septic shock admitted to the intensive care unit for longer than 72 h. Impacts of circulating nicotinamide adenine dinucleotide dehydrogenase subunit-6 (ND6) upon clinical outcomes were analyzed. Next, the role of ND6 in PMN chemotaxis was investigated using isolated human PMNs. Studying plasma samples from 97 patients with septic shock, we found that circulating ND6 levels at admission were independently and highly associated with the development of secondary infection (odds ratio = 30.317, 95% CI: 2.904 to 316.407, P = 0.004) and increased 90-d mortality (odds ratio = 1.572, 95% CI: 1.002 to 2.465, P = 0.049). In ex vivo experiments, ND6 pretreatment suppressed FPR1-mediated PMN chemotactic responses to bacterial peptides in the presence of multiple cytokines and chemokines, despite increased nondirectional PMN movements. Circulating mtFPs appear to contribute to the development of secondary infection and increased mortality in patients with septic shock who survive their early hyperinflammatory phase. The increased susceptibility to secondary infection is probably partly mediated by the suppression of FPR1-mediated PMN chemotaxis to secondary infected sites.

Background. The Vasoactive-Inotropic Score (VIS) is an objective clinical tool used to quantify the need for cardiovas-cular support in children and adolescents after surgery and to predict prognosis of pediatric septic shock. Considering the post-cardiac arrest syndrome (PCAS) is a sepsis-like syndrome, we aimed to inves-tigate the correlation between VIS and in-hospital mortality in out-of-hospital car-diac arrest (OHCA) patients who achieved a sustained return of spontaneous circula-tion (ROSC) and admitted to the intensive care unit (ICU).Methods. A retrospective chart review of 504 OHCA patients who were admitted to the emergency room with OHCA from Jan 2015 to Dec 2016 was done. VIS was calculated with the recorded administra-tion rate of the drugs on electronic medi-cal record at the same time during the first 24 hours in ICU. The highest value of VIS in 24 hours (24hr-peak VIS) was used for investigating the correlation between VIS and in-hospital mortality.Results. Among 504 OHCA patients, 166 patients were admitted to the intensive care unit and 116 patients died during hospital stay. The probability of in-hospital mortality was significantly higher when 24hr-peak VIS was higher than 33.3 [Odds ratio (OR) = 3.18, 95% CI = 1.22 – 8.29, p value = 0.018]. Conclusion. 24hr-Peak VIS could be a good scoring system for predicting in-hospital mortality in OHCA patients who admit-ted to ICU. The AUC was 0.762 (95% CI = 0.690 to 0.825) and the optimal cut-off values were 33.3 (sensitivity 0.764, speci-ficity 0.610).

Carbon nanotube (CNT) membranes are considered as next-generation membranes for desalination. Among the various types of CNT membranes, vertically aligned (VA) CNT membranes provide rapid water transport. However, when the water permeability of VA CNT membranes are compared with those of the commercial membrane, the VA CNT membranes only showed slightly higher water permeability due to their low pore densities. Additionally, the applicability of VA CNT membranes for desalination has been limited due to their larger pore sizes. Herein, we improved VA CNT membranes in terms of the desalination potential, flux enhancement, and scale-up. For the desalination potential, graphene oxide (GO) or polyamide (PA) were coated on a VA CNT membrane as a selective layer, which showed approximately 40–65% NaCl rejection, respectively. A pretreatment polyelectrolyte coating for a GO-coated VA CNT membrane increased the water permeability by approximately 50%. For the flux enhancement, the water permeability of a V...

The objective of this study was to compare the efficacy of cardiopulmonary resuscitation (CPR) with 120 compressions per minute (CPM) to CPR with 100 CPM in patients with non-traumatic out-of-hospital cardiac arrest. We randomly assigned patients with non-traumatic out-of-hospital cardiac arrest into two groups upon arrival to the emergency department (ED). The patients received manual CPR either with 100 CPM (CPR-100 group) or 120 CPM (CPR-120 group). The primary outcome measure was sustained restoration of spontaneous circulation (ROSC). The secondary outcome measures were survival discharge from the hospital, one-month survival, and one-month survival with good functional status. Of 470 patients with cardiac arrest, 136 patients in the CPR-100 group and 156 patients in the CPR-120 group were included in the final analysis. A total of 69 patients (50.7%) in the CPR-100 group and 67 patients (42.9%) in the CPR-120 group had ROSC (absolute difference, 7.8% points; 95% confidence interval [CI], -3.7 to 19.2%; P = 0.183). The rates of survival discharge from the hospital, one-month survival, and one-month survival with good functional status were not different between the two groups (16.9% vs. 12.8%, P = 0.325; 12.5% vs. 6.4%, P = 0.073; 5.9% vs. 2.6%, P = 0.154, respectively). We did not find differences in the resuscitation outcomes between those who received CPR with 100 CPM and those with 120 CPM. However, a large trial is warranted, with adequate power to confirm a statistically non-significant trend toward superiority of CPR with 100 CPM. (Clinical Trial Registration Information: www.cris.nih.go.kr, cris.nih.go.kr number, KCT0000231), Graphical Abstract

Mannitol, an osmotic diuretic, has been used to prevent acute kidney injury (AKI). However, studies have found divergent effects of intraoperative mannitol administration on postoperative AKI. We therefore evaluated the effects of intraoperative mannitol administration on AKI after robot-assisted laparoscopic radical prostatectomy (RALP) in prostate cancer patients. A total of 864 patients who underwent RALP were divided into mannitol (administered at 0.5 g/kg) and no-mannitol groups. Demographics, cancer-related data, preoperative laboratory values, intraoperative data, and postoperative outcomes such as AKI, chronic kidney disease at 12 months postoperation, duration of hospital stay, and intensive care unit admission rate and duration of stay were compared between the 2 groups using propensity score matching analysis. To determine the risk factors for AKI after RALP, univariate and multivariate logistic regression analyses were performed. Postoperative AKI was defined according to the Kidney Disease: Improving Global Outcomes criteria. After performing 1:1 propensity score matching, the mannitol and no-mannitol groups included 234 patients each. The overall incidence of AKI after RALP was 5.1% and was not significantly different between the no-mannitol and mannitol groups in the propensity score-matched patients (13 [5.6%] vs. 11 [4.7%], P = .832). Univariate logistic regression analysis revealed that body mass index and operative time were associated with AKI in 864 patients who underwent RALP. However, intraoperative mannitol administration was not associated with AKI after RALP (P = .284). Multivariate logistic regression analysis revealed that operative time was significantly associated with AKI after RALP (odds ratio = 1.013, P = .001). The incidence of chronic kidney disease (13 [5.6%] vs. 12 [5.1%], P = 1.000) and other postoperative outcomes were not also significantly different between the no-mannitol and mannitol groups in the propensity score-matched patients. Intraoperative mannitol administration has no beneficial effect on the prevention of AKI after RALP in prostate cancer patients. This result provides useful information for clinical practice guidelines regarding intraoperative mannitol use.

SnO 2 thin films were deposited on fused silica substrate by pulsed laser deposition under transverse magnetic field. We have explored the effects of magnetic field and ablation laser wavelength on the optical properties of laser-induced plasma plume and structural characteristics of the deposited SnO 2 films. Optical emission from the plume was monitored using an optical fiber to examine the influence of magnetic field on the population of the excited neutral and ionic species and their decay with times after laser ablation. Also, we employed photoluminescence, x-ray diffraction, and UV-Vis absorption to characterize SnO 2 films. SnO 2 is n-type semiconducting material with a wide bandgap of 3.6 eV at room temperature. Since SnO 2 has high transparency in visible region and electric conductivity, it has diverse applications in gas sensors, solar cells, transparent conducting electrodes, and optoelectronic devices

Carbon and nitrogen co-doped sodium titanate nanotubes (C,N-TNT) active under simulated solar light are synthesized by a simple two-step process comprising an alkaline hydrothermal technique followed by calcination. Different samples of C,N-TNT with varied dopant concentrations are achieved by changing the amount of urea as a nitrogen and carbon dopants. The photocatalysts are characterized using numerous experimental techniques, and under simulated solar light investigated for the photocatalytic conversion of CO2 and water vapor to CH4. The C,N-TNT sample with an intermediate doping concentration yields the maximum methane yield of 9.75 μmol/g h. The key factors contributing in the improvement of photocatalyst performance includes light absorption, surface area and Na+ ions concentration in TNT acting as CO2 adsorption site and photogenerated electrons recombination centers. The higher doping levels results in lower specific surface areas leading to decrease in photocatalyst performance. Our results suggest co-doping of nanostructured photocatalysts is an excellent pathway for improving textural and photocatalytic properties for the respective application domain.

We report on the fabrication of patterned flexible graphene devices via a facile direct transfer of bi-layer graphene grown on alumina (Al2O3) substrate, and the use of Ag nanowire stickers as flexible electrodes. Patterned polydimethylsiloxane (PDMS) stamps coated with vaporized dimethylformamide (DMF) are utilized to transfer as-grown graphene directly onto a flexible polyethylene terephthalate (PET) substrate. The facile direct transfer is attributed to the enhanced adhesion of the bi-layer graphene to PDMS, due to DMF-coating, as well as the weak adhesion between the bi-layer graphene and the Al2O3 substrate. In this way, flexible patterned graphene devices have been fabricated with Ag nanowire stickers as electrodes. Stable electrical conduction characteristics were measured over repetitive bending with a bending radius down to 5 mm.

In recent years, there has been a growing interest in nanostructure membranes made of vertically aligned carbon nanotubes (VA-CNT) due to their potential of high water permeability. Nevertheless, membrane fouling is one of the most critical issues in these VA-CNT membranes. Accordingly, this study mainly focused on understanding of membrane fouling of VA-CNT membranes, which were prepared by thermal chemical vapor deposition (CVD) technique. Surface modification by graft-polymerization of methacrylic acid (MA) was attempted to not only retard membrane fouling but also improve solute rejection. The resistance-in-series model was applied to characterize the properties of fouling layers. BSA (bovine serum albumin) was used as the model foulant. Results indicated that the VA-CNT membranes had higher fouling propensity than polymeric membranes. After surface modification, however, irreversible fouling was significantly reduced in the VA-CNT membranes, which was attributed to an increase in hydrophilicity and surface charge. The rejection of BSA by VA-CNT membrane also increased after surface modification, suggesting that the surface charge played an important role in the rejection of charged molecules.

The photophysical properties of CuInxGa1-xS2 (CIGS) thin films, prepared by solution-based coating methods, are investigated to understand the correlation between the optical properties of these films and the electrical characteristics of solar cells fabricated using these films. Photophysical properties, such as the depth-dependent band gap and carrier lifetime, turn out to be at play in determining the energy conversion efficiency of solar cells. A double grading of the band gap in CIGS films enhances solar cell efficiency, even when defect states disturb carrier collection by non-radiative decay. The combinational stacking of different density films leads to improved solar cell performance as well as efficient fabrication because a graded band gap and reduced shunt current increase carrier collection efficiency. The photodynamics of minority-carriers suggests that the suppression of defect states is a primary area of improvement in CIGS thin films prepared by solution-based methods.

In the current work, stable prenucleated PbS quantum dots (QDs) with a sub-nanometer (0.8 nm) size have been successfully synthesized via a systematically designed experiment. A detailed analysis of critical nucleation, growth, and stability for such ultrasmall prenucleated clusters is done. The experimental strategy is based on controlled concentration, temperature and injection of respective precursors, thus enabling us to control nucleation rate and separation of stable sub-nanometer PbS QDs with size 0.8 nm. Significantly, by providing additional thermal energy to sub-nanometer PbS QDs, we achieved the fully nucleated cubic crystalline structure of PbS with size of around 1.5 nm. The size and composition of the prenucleated QDs are investigated by sophisticated tools like X-ray photoelectron spectroscopy (XPS) and medium energy ion scattering (MEIS) spectroscopy which confirms the synthesis of PbS with Pb2+ rich surface while the UV-Vis spectroscopy and X-ray diffraction (XRD) data suggests an alternative crystallization path. Non-classical nucleation theory is employed to substantiate the growth mechanism of prenucleated PbS QDs.

Direct contact membrane distillation (DCMD) is a membrane distillation (MD) configuration where feed and distillate directly contact with a hydrophobic membrane. Depending on its operating conditions, the hydraulic pressures of the feed and distillate may be different, leading to adverse effects on the performance of the DCMD process. Nevertheless, little information is available on how hydraulic pressure affects the efficiency of DCMD. Accordingly, this paper investigates the effect of external hydraulic pressure on the process efficiency of DCMD. Gas permeabilities of MD membranes were measured to analyze the effect of membrane compaction by external pressure. Mass transfer coefficients were calculated using experimental data to quantitatively explain the pressure effect. Experiments were also carried out using a laboratory-scale DCMD set-up. After applying the pressure, the cross-sections and surfaces of the membranes were examined using a scanning electron microscope (SEM). Results showed that the membrane structural parameters such as porosity and thickness were changed under relatively high pressure conditions (&gt, 30 kPa), leading to reduction in flux. The mass transfer coefficients were also significantly influenced by the hydraulic pressure. Moreover, local wetting of the membranes were observed even below the liquid entry pressure (LEP), which decreased the rejection of salts. These results suggest that the control of hydraulic pressure is important for efficient operation of DCMD process.

Gold nanoparticle (AuNP) solution prepared by laser ablation in liquid (LAL) was irradiated by ns laser pulses to investigate the wavelength dependence on the size distribution of AuNPs and long-term stability of post-irradiated AuNP solutions. We have employed 266, 355, 532, and 1064 nm lasers for post-irradiation source and found considerable wavelength dependence in the size distribution and stability of laser-generated AuNPs. Post-irradiation at 355 nm was most effective to reduce the size distribution and to enhance the stability. The classical Derjaguin–Landau–Verwey–Overbeek theory was employed to explain the anomalous stability at 355 nm.

Polyynes were prepared by liquid laser ablation of a graphite target in deionized water at different laser wavelengths (266, 355, 532, and 1064 nm) and energies (20 and 40 mJ) as well as ablation times (up to 60 min). They were identified by analyzing their ultraviolet absorption spectra and the amount of polyynes so produced turned out to increase at longer wavelength. Also, in order to investigate the effects of various physical parameters on the linear carbon chain length, we compared the branching ratios between C 6 H 2 , C 8 H 2 , and C 10 H 2 .

Membranes utilizing carbon nanotubes (CNTs) as their pores have been emerged as a novel technique for water and wastewater treatment. CNTs are nanometer–diameter cylinders, allowing fast transport of water molecular and other fluid due to their strong hydrophobic characteristics. A few studies have been done for developing membranes embedding single-wall or multiwall nanotubes and simulating their performance theoretically using molecular dynamics. Nevertheless, only a limited number of experimental works were attempted to analyze the transport phenomena inside the CNT membranes due to lack of techniques for quantitative interpretation of the experimental results. Accordingly, this study aimed at developing protocols to quantify the efficiency of CNT membranes and apply them for better understanding of transport mechanisms of the CNT membranes. Membranes made of vertically aligned CNTs, which has 3–5 nm inner diameter and 150∼250 μm length, were used. Special experimental techniques were applied ...

Recently due to the increase in the construction of the steel–concrete composite structures, researches on shear connector which is capable of composite behavior of two members have been widely studied. This study evaluated the behavior of Y-type perfobond rib shear connector which is superior in shear resistance and ductility than conventional perfobond rib shear connector. Also, it suggested a shear resistance equation based on the push-out test. Firstly, various types of the proposed Y-type perfobond rib shear connectors have been examined to evaluate the effect on design variables such as strength of concrete, transverse rebar, thickness of rib, and Y-shape angle. As a result, the experiment showed that the higher the concrete strength, the shear resistance increased, while ductility decreased. In addition, transverse rebar significantly impacted both shear resistance and ductility to increase. Moreover, as thickness of ribs increased, shear resistance increased and ductility decreased. It was also proven that Y-shape angle has an effect on shear resistance and ductility to grow. Furthermore, it was indicated that Y-type perfobond rib shear connector has higher shear resistance and ductility than the conventional perfobond rib shear connector by comparing and estimating the experimental results. Lastly, the effect of bearing resistance, transverse rebar, dowel resistance by holes, and dowel resistance by Y-shape ribs on shear resistance was estimated by regression analysis. Through the result, the shear resistance equation was suggested to predict shear resistance of Y-type perfobond shear connector.

(≥ 99.0%), n-octane (≥ 99.0%). These solvents were purchased from Sigma-Aldrich and used without further purification. The surface of the graphite target was polished with 1200grade emery paper prior to laser irradiation using a Qswitched Nd:YAG laser (Continuum, Surelite I, λ = 1064 nm, pulse duration 5 ns) operated at 10 Hz. The energy of the laser was maintained at 20 mJ/pulse in order to avoid generation of splashes. The laser beam was loosely focused using a lens with a focal length of 300 mm and the typical irradiation time was 20 min. The solution was stirred during the ablation using a magnetic stirrer. The target was also continuously rotated to minimize the effect of target aging and to provide some stirring effect. The optical properties of the nascent polyynes solutions were studied at room temperature in various solvents by a UV-vis absorption spectrophotometer (Shimadzu UV1800) and normal Raman spectra were recorded by a spectrophotometer (HORIBA T64000).

In the growing standard of people`s lives, we want desire to create eco-friendly water space what is called the Green Technology that is in the limelight. These green space is introduced the cultural contents and we use the water, music, and nature as tool of emotional verbalism. Presently, when we want to make scenario, water landscape scenario is made by director. but these systems have some disadvantages as the cost and limitation of direction. There is a growing interest in the integrated control system based on PC and Internet. In this paper, it is about fountain control system. Previous research area was only one using programmable logic controller or industrial PC. we proposed the development of intelligent green fountain culture system for healthy emotional self-concept. And we made automatic weather sensing system that is designed by the intelligent green fountain culture system to estimate the time-variant system.

Smart Space is a major currently challenging domain that includes ubiquitous, grid, and pervasive computing to provide intelligence, insight, and vision for emerging world of intelligent environment, products, services and human interaction. Smart Space consists of various objects (devices and applications) and, their extremely tight integration of and coordination between information world and physical resources. In Smart Space, people are allowed to acquire useful information and control devices anytime and anywhere with various smart devices. However the physical world where devices are deployed has much uncertainty and uncontrollable conditions, so that it is impossible to make devices suited to all situations. To achieve user satisfaction and overcome the system failure, devices in Smart Space must be dependable, secure, safe, and efficient, and operate in real-time. In addition, they must be scalable, cost-effective and adaptive. Especially, to deal with uncertainty and uncontrollable condition, devices in Smart Space could be more intelligent in the adaptation. In this paper, we propose an agent-based self-adaptation architecture for implementing smart devices in Smart Space. A self-adaptive smart device reasons about its state and environment, and adapts itself at runtime automatically and dynamically in response to changes. Also we present an adaptation mechanism used to implementing a self-adaptive system.

Recently, a music genre classification has been studied. However, experts use different criteria to classify each of these classifications is difficult to derive accurate results. In addition, when the emergence of a new genre of music genre is a newly re-defined. Music as a genre rather than to separate search should be classified as emotional words. In this paper, the feelings of people on the basis of brightness and darkness tries to categorize music. The proposed classification system by applying VCM(Variance Considered Machines) is the contrast of the music. In this paper, we are using three kinds of musical characteristics. Based on surveys made throughout the learning, based on musical attributes(beat, timbre, note) was used to study in the VCM. VCM is classified by the trained compared with the results of the survey were analyzed. Note extraction using the MATLAB, sampled at regular intervals to share music via the FFT frequency analysis by the sector average is defined as representing the element extracted note by quantifying the height of the entire distribution was identified. Cumulative frequency distribution in the entire frequency rage, using the difference in Timbre and were quantified. VCM applied to these three characteristics with the experimental results by comparing the survey results to see the contrast of the music with a probability of 95.4% confirmed that the two separate.

The triplet state of 4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine ( m -MTDATA) and the dynamics of the singlet and the triplet states were examined to understand the confinement effect of m -MTDATA as host materials for phosphorescent organic light-emitting diodes. The time-resolved photoluminescence spectra revealed phosphorescence at approximately 480 nm (2.58 eV). The time constant of the T 1 state was 1.2 μs. The dynamics of delayed fluorescence was closely related to that of phosphorescence. The triplet energy of a green phosphorescent sensitizer was well-confined in the m -MTDATA host, which suggests the application of m -MTDATA as possible host materials.

(a) Photoluminescence spectrum of the ZnO powders ob-tained with a He-Cd laser (325 nm). Inset shows the transmission electron microscopy (TEM) image of the ZnO powders used for the measurements. (b) Emission spectrum of the ZnO powders obtained by intensive excitation of fundamentals, such as 800, 750, and 710 nm. The dotted line indicates the band gap of ZnO. (c) Refractive index and its difference related term as a function of the wavelength.

We fabricated hexagonal arrays of Co/Pt nanodots on Si surfaces by pulsed laser deposition (PLD) using cylindrically phase-separated polystyrene-b-poly(methylmethacrylate) (PS-b-PMMA) diblock copolymer thin films as templates after the removal of PMMA. The size and the separation of the nanodots were 23 and 40 nm, respectively, and the density of the nanodots was 1.5 x 10(11)/cm2. The magnetic properties of nanodot arrays measured by vibrating sample magnetometer were compared with those of PLD grown film. The films showed magnetic anisotropy with an easy axis in the in-plane direction, whereas no noticeable anisotropy was observed for nanodot arrays. In addition, the saturation magnetization (Ms) of both the Co/Pt nanodots and the film increased with the Pt content.

By adopting a fast photography and time-resolved optical emission spectrometry, we have investigated the effects of transverse magnetic field on the expansion dynamics and enrichment of Zn atoms and Zn + ions in a plume produced by laser ablation of a Zn target in oxygen atmosphere. Plume splitting due to the magnetic field was apparent but the splitting patterns of Zn and Zn + were totally different. The surface morphology and photoluminescence characteristics also changed significantly. In particular, the growth rate increased by as much as 2.4–4.3 times compared to the conventional PLD method.

By adopting a time-resolved optical emission spectrometry, we have investigated the effects of transverse magnetic field on C2 and CN molecules produced by laser ablation of a graphite target in nitrogen atmosphere. We found that the spectroscopic temperatures of both species, obtained via simulation of the optical emission spectra, as well as their emission intensities from the electronically excited states increased significantly in the presence of a magnetic field. The cyclotron radii and frequencies for electrons and ions were estimated to explain the increase in the number of collisions in the laser-produced carbon plasma plume under a magnetic field.

Formation mechanisms and expansion dynamics of silicon-carbon mixed cluster ions (SinCm+) in a laser-produced plasma plume produced by laser (λ=1064 nm) ablation of a SiC target in high vacuum were investigated by time-of-flight quadrupole mass spectrometry. Space- and time-resolved laser-plume interaction was examined by illuminating the plume with a time-delayed and line-focused. Ultraviolet laser pulse. Si2C was the dominant photodissociation product of silicon carbide cluster ions. Silicon-carbon mixed clusters turned out to be formed via association of atomic species in a region away from, not in front of, the target surface after a certain delay time.

∆v = 0) were simulated to obtain the vibrational and rotational temperatures ofthe electronically excited species at various laser fluences and distances from the target. The spectroscopictemperatures of both molecules were found to be nearly independent of the laser fluence. The temperature ofCN molecules was peaked in the mi ddle of the plume while that of C

Mass spectral distributions and time-of-flight spectra of Cn+ (n=1–24) ions escaping from a carbon plasma plume generated by laser (λ=1064 nm) ablation of a graphite target are analyzed to shed light on their formation mechanisms, expansion dynamics, and laser–plume interaction. In particular, by shining the whole or a slice of the plume with a photodissociation laser (λ=266 nm) delayed with respect to the ablation laser, we examine the effects of the laser–plume interaction on the mass distribution as well as photodissociation channels of carbon-cluster cations. Also, we present experimental data that show a clear linear dependence of the velocities of Cn+ ions on 1/M. This result confirms that Cn+ ions are mainly accelerated by a transient local electric field in the plume.

Silver nanoparticles were synthesized by laser (Nd:YAG, λ =1064 nm) ablation of a silver target immersed in various concentrations of NaCl solutions as well as in neat water. The concentration dependence of the surface plasmon absorption at around 400 nm was examined by analyzing the absorbance and peak shape. Significant changes in the peak intensity and full width at half maximum (FWHM) were observed. Typically, the size of the silver nanoparticles produced in 5 mM NaCl solution ranged from 5 to 50 nm, with an average size of 26 nm. Also, fragmentation of silver nanoparticles by absorption of 355 nm laser light was found to be highly effective.

Mass spectroscopic studies on a reactive laser ablation of YBa2Cu3O7−x at 266 and 1064 nm in a pulsed oxygen jet have been performed by direct sampling of ions escaping from a laser-induced plasma (plume). Energetics of the ions is studied by using a time-of-flight (TOF) quadrupole mass spectroscopy. TOF spectra of metal ions consist of a fast and a slow component, but TOF spectra of metal oxide ions show single broad distributions. Significant changes in the relative enrichment of metal oxide and oxygen ions and their TOF distributions are observed by adding oxygen molecules to the plume. Formation mechanisms of each ion are investigated by analyzing the TOF spectra with O2 pulse on and off. The dependences of the TOF spectra on the laser wavelengths and their fluences are also examined to elucidate the acceleration mechanisms of ions as well as photochemical phenomena in the plume.

Formation mechanisms of atomic and oxide ions in a plume (laser-induced plasma) produced by the laser ablation of a YBa2Cu3O7-x (YBCO) target was studied by time-of-flight (TOF) analysis. The dependence of the TOF spectra on the laser wavelengths (266 nm and 1064 nm) was examined to elucidate photochemical phenomena in the plume. Significant changes in the relative enrichment of metal oxide and oxygen ions as well as their TOF distributions were observed by the injection of an oxygen jet to the plume, which induces reactive scattering of the YBCO plume and the oxygen jet.

Mass spectroscopic studies on a reactive laser ablation of graphite at 1064 nm in a pulsed oxygen jet have been performed. Significant changes in the relative enrichment of carbon ions including anomalous enrichment of C2+ ions as well as formation of CO+, C2O+, and C3O+ ions are observed. Collision-induced dissociation and reactive scattering of carbon ions prevail by injection of the oxygen jet to the carbon plume. Energetics of the ions is studied by using a time-of-flight quadrupole mass spectroscopy. Time-of-flight (TOF) spectra of each carbon ion consist of a fast and a slow component, which are considered to represent different formation mechanisms. By analyzing the changes of TOF spectra as a function of the delay time between the laser pulse and oxygen jet, we examine the effects of collisions on the formation of carbon ions.

The laser ablation of pyrolytic boron nitride (pBN) target was investigated by quadrupole mass spectroscopy. The laser-correlated ion mass spectra and time-of-flight (TOF) spectra were obtained. B + and B 2 + ions were detected but N + , N 2 + , or BN + ions were not observable. Instead, neutral N 2 molecules were detected. The velocity of B + ions and temperature of the plume were derived by shifted Maxwell–Boltzmann fitting of the TOF spectra of B + ions. At the laser fluence of 0.7 J/cm 2 , the velocity of B + ions was 21.7 km/s and the temperature was 15 765 K. Also studied were the effects of the retarding field on the energetics of B + ions. The space-charge effect was found to influence the dynamics of plume propagation significantly. The reactive laser ablation under N 2 atmosphere has been attempted by using a pulsed valve synchronized with the laser pulse.

Conventional, intravenous, patient-controlled analgesia, which is only administered by demand bolus without basal continuous infusion, is closely associated with inappropriate analgesia. Pharmacokinetic model-based dosing schemes can quantitatively describe the time course of drug effects and achieve optimal drug therapy. We compared the efficacy and safety of a conventional dosing regimen for intravenous patient-controlled analgesia that was administered by demand bolus without basal continuous infusion (group A) versus a pharmacokinetic model-based dosing scheme performed by decreasing the dosage of basal continuous infusion according to the model-based simulation used to achieve a targeted concentration (group B) following robot-assisted laparoscopic prostatectomy. In total, 70 patients were analyzed: 34 patients in group A and 36 patients in group B. The postoperative opioid requirements, pain scores assessed by the visual analog scale, and adverse events (eg, nausea, vomiting, pruritis, respiratory depression, desaturation, sedation, confusion, and urinary retention) were compared on admission to the postanesthesia care unit and at 0.5, 1, 4, 24, and 48 h after surgery between the 2 groups. All patients were kept for close observation in the postanesthesia care unit for 1 h, and then transferred to the general ward. The fentanyl requirements in the postanesthesia care unit for groups A and B were 110.0 ± 46.4 μg and 77.5 ± 35.3 μg, respectively. The pain scores assessed by visual analog scale at 0.5, 1, 4, and 24 h after surgery in group B were significantly lower than in group A (all P

We have fabricated Er-doped amorphous SiOx films by laser ablation of a Si:Er2O3 target in He atmosphere. The photoluminescence intensity at 1.54 μm was highly dependent on the oxygen content in the film, which turned out to be changed significantly by the ambient He pressure. Also, we have adopted time-of-flight quadrupole mass spectroscopy to obtain kinetic energies of ionic species in a plume produced by laser ablation. Si and Er ions do not overlap spatially as they expand toward the Si substrate and Er ions impinge on the preformed SiOx layer.

Skills related to cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use by lay responders decay rapidly after training, and efforts are required to maintain competence among trainees. We examined whether repeated viewing of a reminder video on a mobile phone would be an effective means of maintaining CPR and AED skills in lay responders.In a single-blind case-control study, 75 male students received training in CPR and AED use. They were allocated either to the control or to the video-reminded group, who received a memory card containing a video clip about CPR and AED use for their mobile phone, which they were repeatedly encouraged to watch by SMS text message. CPR and AED skills were assessed in scenario format by examiners immediately and 3 months after initial training.Three months after initial training, the video-reminded group showed more accurate airway opening (P0.001), breathing check (P0.001), first rescue breathing (P=0.004), hand positioning (P=0.004), AED electrode positioning (P0.001), pre-shock safety check (P0.001), defibrillation within 90s (P=0.010), and resuming CPR after defibrillation (P0.001) than controls. They also showed significantly higher self-assessed CPR confidence scores and increased willingness to perform bystander CPR in cardiac arrest than the controls at 3 months (P0.001, P=0.024, respectively).Repeated viewing of a reminder video clip on a mobile phone increases retention of CPR and AED skills in lay responders.

Dynamic Software Update (DSU) is an advanced software practice to change a running program with imposing negligible service interruption while updating. In this paper, we present DSUEnhancer, a DSU implementation for resource-constrained C programs like embedded software. DSUEnhancer generates a patch file off-line and loads it into the dynamic memory of an updated program on-line. In particular, DSUEnhancer is relatively lightweight in terms of memory and CPU usage and runs on the ARM architecture with the gcc cross compiler.

In this regard, identification of chemical species in theplume is essential to establis h an optimum condition to growhigh-quality thin films. But detailed mass-spectral analysisof the products in the plume produced for PLD is quite rarebecause the typical pressure in PLD is in the range of 0.1 to1 Torr, at which mass spectrometers are not applicable.In case of the Ti + N

As the number of mobile devices accessing large-scale WLANs such as campus and metropolitan area networks increases, the need for load balancing among the cells becomes crucial. In addition, the network must also support some minimum handoff tolerance defined by an application. This paper proposes a new metric that provides load balance as well as timely handoffs for WLANs by taking into account both direct and hidden node collisions.

The autonomous military robot system is a complex hybrid system which is difficult to represent by ordinary modeling frameworks due to its continuous behaviors. In this paper, we present a case study to formally model this system using CHARON that is a hierarchical modeling framework for hybrid systems. To precisely capture all the behaviors of the military robot system, we propose several extensions for the CHARON framework.

We have used the method of Shapiro, Hepburn, and Brumer to control the ionization rates of HCl and CO. This method is based on the principle of quantum mechanical interference between two competing paths. In this case the two paths are one‐ and three‐photon excitation of an intermediate Rydberg state. A vacuum ultraviolet (VUV) (110–115 nm) laser beam was produced by third‐harmonic generation from an UV beam in Kr gas. The relative phases of the two beams were controlled by passing them through a chamber containing either Ar or H2. The laser beams were focused into a molecular beam, and the ionization products were measured in a time‐of‐flight mass spectrometer. As the pressure of the phase‐tuning gas was varied, the ionization signal was found to oscillate with a period that is proportional to the difference of the indices of refraction of the tuning gas at the UV and VUV wavelengths. We have applied this technique to transitions involving different intermediate electronic states [the j 3Σ−(0+), H 1Σ+(0+...

We present the integration of a cyclo olefin copolymer microfluidic chip with electrochemical pumps and an SU-8 tip for electrospray ionization mass spectrometry. The electrochemical pump, using electrolysis as an internal pressure source, was fabricated directly on the surface of the polymer chip. The triangular SU-8 emitter tip was fabricated on a glass wafer using standard photolithography. After release from the glass wafer, this tip was aligned to the microchannel and bonded between two polymer plates. The electrochemical pump and the electrospray tip were tested with electrospray ionization mass spectrometry. Mass spectrometry confirmed the stability of the electrochemical pump and the electrospray tip.

This paper proposes a medium access control (MAC) algorithm, called Cooperative Diversity MAC (CD-MAC), which exploits the cooperative communication capability to improve robustness in wireless ad hoc networks. In CD-MAC, each terminal proactively selects a relay for cooperation and lets it transmit simultaneously when it is beneficial in mitigating interference from nearby terminals and thus improving the network performance. For practicability, CD-MAC is designed based on the widely adopted IEEE 802.11 MAC. System-level simulation study shows that CD-MAC significantly outperforms the original IEEE 802.11 MAC in terms of packet delivery ratio.

We examined the laser ablation dynamics of silver target in aqueous phase to explore the effects of laser power, ambient electrolytes, and magnetic field on the formation and expansion of laser-induced plasma plume, bubbles, and nanoparticles. The lifetime of the plasma emission increased with magnetic field and electrolytes, while they had no influence on the conversion of laser energy to the energy of laser-induced bubbles formed thereafter. The size of the bubbles was dependent only on the laser power.

Computer based multipoint teleconferencing systems consist of terminals with audio/video codecs and network interfaces, and they make participants communicate with each other. For interoperation of these systems on LAN (local area Network), ITU-T presented H.323 recommendation. H.323 consists of encoding and decoding algorithms of audio and video, call processing protocol, data communication protocol, and control protocol for multimedia communication. The call processing protocol is H.225 the data communication protocol is RTP (real time protocol) and the control protocol is H.245. In this paper, we present the procedure and the implementation structure of the control protocol for multipoint audio-video teleconferencing systems.

The development of microfluidic platforms broke the barrier for rampant growth of on-chip biomarker identification in the field of disease diagnostics. Unfortunately, the amplification of nucleic acids directly from raw patient blood has yet to find a simple but complete design on a point-of-care microfluidic device. Here we report a technological approach to detect circulating DNA typically found in whole blood of cancer patients through an on-chip blood-plasma separation, filtration, reagent mixing, and PCR amplification. Raw patient sample blood will first be placed through a self-driven, gravitational and drag powered filtration system, where separation times as low as 10 minutes per 5 μL of blood can be achieved. Plasma separation coupled with nitrocellulose filters will lead to a 99% pure plasma product. Patient plasma can then be properly placed into micro-chambers, where they will be exposed to corresponding lyophilized reagents and enzymes. With each well equipped to an individual micro-heater, concentrated thermo-cycling induces DNA amplification by following golden-standard PCR methodology on a minute-scale basis. Amplification of nucleic acids in the steps indicated above present a simple device design for diagnosis of DNA biomarkers from patient to PCR. To thoroughly accomplish all desired tasks in a direct and efficient manner, the components of an on-chip PCR platform will include a simple yet powerful blood separation method, lyophilized reagent storage, and micro-heated thermo-cycling.

(a) The transmission electron microscopy (TEM) image of the ZnO powders used for the measurements. (b) Photoluminescence spectrum of the ZnO powders obtained with a He-Cd laser (325 nm). (c) Emission spectrum of the ZnO powders obtained with excita tion of 800 nm. For comparison, photoluminescence spectrum obtained with excitation of 325 nm is also shown. The inset shows a wide wav elength range of the emission spectrum obtained with excitation of 800 nm.

Coherent control of the ionization of HCl was achieved by simulataneous 3+1 and 1+1 multiphoton excitation in a molecular beam machine, using either three 336 nm photons or one 112 nm photon to resonantly excite the intermediate j 3Σ−(Ω=0+) state. The phase difference between the two laser beams was continuously varied by passing the radiation through a cell containing either Ar or H2 gas.