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Vocal fold scarring is a major cause of dysphonia. Vocal fold fibroblasts (VFFs) and the TGF-β signaling pathway play important roles in scar formation. Eupatilin, a chromone derivative of the Artemisia species, is a traditional folk remedy for wound healing. However, until recently, few studies investigated the therapeutic effects of eupatilin. We investigated the antifibrogenic effects of eupatilin on TGF-β1-treated human vocal fold fibroblasts (hVFFs). The optimal concentration of eupatilin was determined by a cell viability assay. Western blotting was used to measure the expression of alpha-smooth muscle actin during myofibroblast differentiation, fibronectin (FN), collagen type I (Col I), and collagen type III (Col III) extracellular matrix proteins, and Smad2, Smad3, and p38 in the fibrotic pathway. Measurements were made before and after eupatilin treatment. Eupatilin at 100 nM was shown to be safe for use in hVFFs. TGF-β1 induced hVFFs to proliferate and differentiate into myofibroblasts and increased Col III and FN synthesis in a time- and dose-dependent manner. Eupatilin suppressed TGF-β1-induced hVFF proliferation and differentiation into myofibroblasts through the Smad and p38 signaling pathways. Furthermore, eupatilin inhibited TGF-β1-induced FN, Col I, and Col III synthesis in hVFFs. Our in vitro findings show that eupatilin effectively suppressed TGF-β1-induced fibrotic changes in hVFFs via the Smad and p38 signaling pathways. Thus, eupatilin may be considered a novel therapeutic agent for the treatment of vocal fold fibrosis.

We evaluated the cost-effectiveness of a genotype-guided strategy among patients with acute coronary syndromes using a decision-tree model based on the Singapore healthcare payer’s perspective over a 1-year time horizon. Three dual antiplatelet strategies were considered: universal clopidogrel, genotype-guided, and universal ticagrelor. The prevalence of loss-of-function alleles was assumed to be 61.7% and model inputs were identified from the literature. Our primary outcome of interest was incremental cost-effectiveness ratio (ICER) compared to universal clopidogrel. Both genotype-guided (72,158 SGD/QALY) and universal ticagrelor (82,269 SGD/QALY) were considered cost-effective based on a willingness-to-pay (WTP) threshold of SGD 88,991. In our secondary analysis, the ICER for universal ticagrelor was 114,998 SGD/QALY when genotype-guided was taken as a reference. Probabilistic sensitivity analysis revealed that genotype-guided was the most cost-effective strategy when the WTP threshold was between SGD 70,000 to 100,000. Until more data are available, our study suggests that funding for a once-off CYP2C19 testing merits a consideration over 1 year of universal ticagrelor.

AlGaN/GaN high electron mobility transistors (HEMTs) are fabricated using a gate recess process and a surface treatment with tetramethylammonium hydroxide (TMAH) prior to gate metal deposition. Electrical characterizations show improved extrinsic transconductance and saturation current, as well as more uniform off-state behavior with reduced off-current by a factor of 3.5 and gate leakage current by a factor of 4.2 in the devices with TMAH treatment. The analyses based on atomic force microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy show that the TMAH treatment effectively reduces the roughness of the recess-etched AlGaN surface and removes the native oxide layer on the AlGaN surface, suggesting a simple and viable route towards the fabrication of gate-recessed HEMTs based on AlGaN/GaN heterostructure with improved controllability and uniformity.

This paper proposes a novel skewed-beam compensation algorithm for a full digital phased array antenna. When a full digital phased array antenna, which is tilted up-or down-ward, radiates a steered horizontal fan beam, the fan beam becomes skewed and needs to be compensated. The simulation results drawn by the compensation algorithm are presented for an arbitrary antenna shape that generates a horizontal fan beam pattern.

International audience; Normally-off AlGaN/GaN-based MOS-HEMT has been fabricated by utilizing damage-free self-terminating tetramethyl ammonium hydroxide (TMAH) recess etching. The device exhibited a threshold voltage of +2.0 V with good uniformity, extremely small hysteresis of ∼20 mV, and maximum drain current of 210 mA/mm. The device also exhibited excellent off-state performances, such as breakdown voltage of ∼800 V with off-state leakage current as low as ∼10−12 A and high on/off current ratio (Ion/Ioff) of 1010. These excellent device performances are believed to be due to the high quality recessed surface, provided by the simple self-terminating TMAH etching. Previous article in issue

The effect of co-evaporated tris(8-hydroxyquinolinato)aluminium:8-hydroxy-quinolinato lithium (Alq3:Liq) on the performance of a photovoltaic (PV) cell was investigated by characterizing the performance of a PV cell fabricated on poly (3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl- C61butyric-acidmethyl-ester (PCBM) bulk heterojunctions with Alq3:Liq as an exciton/holeblocking and electron-injection layer. Inserting Alq3:Liq layer into the PV cell strongly affected the power conversion efficiency (PCE) and fill factor (FF) of the PV cell; i.e., 1-nm-thick Alq3:Liq layer increased the PCE and the FF of the PV cell by 55.22 and 7.15%, respectively, compared with the cell without the Alq3:Liq layer. In particular, the PCE and the short circuit current density (J SC ) of the PV cell with an Alq3:Liq layer were 4.14 and 6.2% higher than those of a 2,9-dimethyl- 4,7-diphenyl-1, 10-phenanthroline (BCP)/LiF bi-layer cell, respectively, because the Liq deposited on Alq3 reduced the electron injection barrier between the workfunction of the aluminum electrode and the lowest unoccupied molecular orbital (LUMO) level of the organic material, resulting in the peak of the binding energy moving toward the high highest occupied molecular orbital (HOMO) level.

The dependence of the weight of the electron-donating material, poly(3-hexylthiophene-2,5-diyl) (P3HT), and electron-accepting material, [6,6]-phenyl C61 butyric acid methyl ester (PCBM), on the photovoltaic characteristics of a polymer photovoltaic (PV) cell was investigated. A P3HT weight varied, the dependence of the power-conversion efficiency (PCE) on the weight of P3HT was similar to that of the short-circuit current (J SC ), but not that of to the open-circuit voltage (V OC ) and the fill factor (FF). That trend is associated with the fact that the absorbance of light and the carrier transport resistance strongly depend on the weight P3HT. In particular, the PCE and J SC of a cell with a specific weight ratio of P3HT to PCBM, i.e., P3HT (0.0266 g):PCBM (0.0133 g), were maximized, 3.48% and 8.43 mA/cm2, which were improvements of 676 and 532%, respectively. The weight P3HT in the P3HT:PCBM blended layer strongly influenced the J SC of the polymer PV cell.

The purposes of this research and development are as follows: first, to provide pleasant driving environments inside tunnels; second, to improve the current illumination environments lacking in diffusion luminance meters to meet tunnel lighting standards; and, third, to reduce the consumption of tunnel lighting energy accounting for approximately 65% of tunnel maintenance costs because of inadequate visual environments and tunnel operations. Further details are listed below. Firstly, an image luminance meter for tunnels that can implement the L20-method which is a tunnel luminance method that follows the international standards of CIE88, which was developed in order to improve and change the existing illumination-based tunnel lighting operation system to a luminance-based system. (The margin of error of below 5% according to the results of a test by an authorized agency and field test). Secondly, early illumination control is possible since the lighting control system that can be operated based on luminance enables interlocking control of the inside and outside of a tunnel using ethernet communication. Thirdly, guidelines for field application of the system are proposed. In addition, the luminance inducers of tunnels are found and the reflexibility of each facility that may reduce luminance of the boundaries is also proposed. Fourthly, as a result of a test bed, power consumption of luminance-based lighting operations decreased by 15.6% compared to illumination-based operations. Applying the feedback controls and maintenance factors of internal/external luminance meters, it reduced by 36.4%. Therefore, we became able to provide a luminance-based lighting operation system that complies with tunnel lighting design standards and provides a visual environment for drivers.

Molybdenum disulfide (MoS2) is an extremely intriguing material because of its unique electrical and optical properties. The preparation of large-area and high-quality MoS2 nanosheets is an important step in a wide range of applications. This study demonstrates that monolayer and few-layer MoS2 nanosheets can be obtained from electrochemical exfoliation of bulk MoS2 crystals. The lateral size of the exfoliated MoS2 nanosheets is in the 5-50 μm range, which is much larger than that of chemically or liquid-phase exfoliated MoS2 nanosheets. The MoS2 nanosheets undergo low levels of oxidation during electrochemical exfoliation. In addition, microscopic and spectroscopic characterizations indicate that the exfoliated MoS2 nanosheets are of high quality and have an intrinsic structure. A back-gate field-effect transistor was fabricated using an exfoliated monolayer MoS2 nanosheet. The on/off current ratio is over 10(6), and the field-effect mobility is approximately 1.2 cm(2) V(-1) s(-1); these values are comparable to the results for micromechanically exfoliated MoS2 nanosheets. The electrochemical exfoliation method is simple and scalable, and it can be applied to exfoliate other transition metal dichalcogenides.

Objective: Secreted protein acidic and rich in cysteine (SPARC) is expressed in most tissues and is also secreted by adipocytes. The associations of SPARC mRNA expression in visceral adipose tissue (VAT), subcutaneous abdominal adipose tissue (SAT), serum SPARC concentration, and metabolic parameters in Korean women are investigated. Design and Methods: This is a cross-sectional study. Fifty-eight women were recruited, of whom 15 women who underwent bariatric surgery for morbid obesity (BMI mean ± SD: 40.2±5.7 kg/m2), 16 who underwent metabolic surgery for type 2 diabetes (BMI: 28.9±4.5 kg/m2), and, as a control group, 27 who underwent gynecological surgery (BMI: 22.7±2.4 kg/m2). Anthropometric variables, metabolic parameters, SPARC mRNA expression in adipose tissue, and serum SPARC concentration were measured. Results: In all subjects, SPARC mRNA expression was significantly higher in SAT than in VAT. Serum SPARC concentrations (mean ± SE) in morbidly obese subjects, subjects with type 2 diabetes, and normal weight subjects were 267.3±40.2 ng/mL, 130.4±33.0 ng/mL, and 53.1±2.8 ng/mL, respectively. SPARC mRNA in SAT was significantly correlated with BMI, whereas SPARC mRNA in VAT was significantly correlated with BMI and VAT area. Serum SPARC concentration was significantly correlated with BMI, waist circumference, total adipose tissue area, and SAT area. After BMI adjustment, serum SPARC concentration was significantly correlated with fasting insulin concentration and HOMA-IR score. Multivariate regression analysis showed that BMI and HOMA-IR were independently associated with serum SPARC concentration. Conclusions: Serum SPARC concentration is significantly correlated with obesity indices and might be influenced by insulin resistance. These findings suggest that SPARC may contribute to the metabolic dysregulation associated with obesity in humans.

We investigated the dependencies of a polymer photovoltaic (PV) cell on the thickness of its 8-hydroxy-quinolinato lithium (Liq) layer. The power conversion efficiency (PCE) of the polymer PV cell shows a trend similar to that of the fill factor (FF), but not to the open-circuit voltage (Voc) and the short-circuit current (Jsc), for various Liq layer thicknesses. This trend is likely associated with the series resistance of the polymer PV cell, which depends on the thickness of the Liq layer. As a result, if the PCE of the polymer PV cells fabricated with a Liq layer is to be enhanced, a specific thickness (in our experiment, ∼1.0 nm) should be used for the Liq layer. In addition, we suggest that the electron injection mechanism of the Liq layer between the small-molecular hole/exciton blocking layer (in our experiment, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP)) and the metal cathode (in our experiment, Al) strongly influences the PCE of polymer PV cells.

The performance of polymer photovoltaic (PV) cells based on poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl-C61 butyric-acid methyl-ester (PCBM) bulk heterojunctions with an NiO x anode buffer layer was investigated. NiO x layers with various thicknesses (i.e., without a layer, 0.5, 1, 2, and 5 nm), were fabricated by oxygen plasma treatment on an evaporated metallic Ni layer under 200 W and 100 sccm for 200 s. The power conversion efficiency (PCE) of the polymer PV cell exhibited a similar trend to the short-circuit current density ( J sc ) and fill factor (FF) but not to open circuit voltage ( V oc ) for various NiO x thicknesses. This tendency is associated with the fact that the light absorption and series resistance of the polymer PV cell depends on the thickness of the NiO x layer. The PCE of the cell with the optimized 1-nm-thick NiO x layer was improved by 68.5% compared to that of the cell without an NiO x layer. With a combination of different techniques of analysis, such as Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS), the fabricated NiO x layer was studied in detail. The NiO x layer between the ITO anode and active layer strongly influenced the PCE of polymer PV cells, which was accounted for by hole-injection and electron-blocking properties.

We investigated the effect of the reflectivity of various metal cathodes on the power-conversion efficiency (PCE) of organic photovoltaic (OPV) cells fabricated with a P3HT:PCBM blended layer. The reflectivity of the cathodes correlated well with the short-circuit current (Jsc) influenced by absorption of visible light reflected from the cathodes; that is, a higher reflectivity of the cathodes led to a higher Jsc. In addition, we analyzed how the surface roughness of a metal cathode influences the performance on the polymer PV cells. As a result, a higher reflectivity and a lower surface roughness of the metal cathodes gave a higher PCE. In addition, it was confirmed that the interface property between the metal cathodes and organic hole/exciton blocking layer strongly influences the PCE of OPV cells.

We investigated the dependency of the power conversion efficiency on the thickness of donor (copper phthalocyanine; CuPc), acceptor (fullerene; C 60 ), and hole/exciton blocking (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline; BCP) layers in the OPV devices fabricated with double small-molecular layers. The power conversion efficiency peaked at a specific layer thickness, ∼12.7 nm for the donor layer, ∼17.5 nm for the acceptor layer, and ∼8.0 nm for the hole/exciton blocking layer. This trend of power conversion efficiency was determined by short-circuit-current rather than open-circuit-voltage after light absorption. In addition, the donor layer thickness was more sensitive than the thickness of the acceptor or hole/exciton blocking layers in improving power conversion efficiency; i.e., ∼330% for the donor layer, ∼118% for the acceptor layer, and ∼112% for the hole/exciton blocking layers.

A monolayer of L10 FePt nanoparticles was fabricated on a polymer film by introducing a Au seed layer prior to the Fe-Pt deposition on the polyimide film. The particle size distribution was tightened from 5.1plusmn1.8 nm to 3.8plusmn1.1 nm by introducing the Au seeds to induce a preferential nucleation of the deposited metal on the preexisting Au particles. Deposition and annealing was repeated so that well-separated hard magnetic nanoparticles with several nanometers in diameter were achieved in a monolayer configuration. The method can be easily extended to a larger area as well as to other alloy systems to create a monolayer of nanoisland structures on a polymer film.

An amorphous Si film with thickness of 350 nm was fabricated on both Cu substrate and Ni film (under layer)/Cu substrate by direct current (DC) and radio frequency (RF) magnetron sputtering. The surface morphology, crystallographic structure and electrochemical properties were investigated. Flat surface was formed in Si/Cu film, whereas in Si/Ni/Cu film a rough surface was formed consisting of Si clusters. In a Si/Li half-cell test with current densities of 210 (0.05 C-rate), 810 (0.2 C-rate) and 4200 mA g−1 (1 C-rate), the surface-modified Si film electrode exhibited a significantly improved cycle performance compared to the Si film deposited on only Cu substrate. LiFePO4/Si full cell tested at current density 85 mA g−1 of (0.5 C-rate) displayed the first charge capacity of 154.0 mAh g−1, corresponding to 90.5% of theoretical capacity of LiFePO4 and the capacity retention of 79.4% at 20th cycle.

We investigated the effect of the thicknesses of the interface layers (here, PEDOT:PSS and LiF) of polymer photovoltaic cells because variations in thickness strongly affect the power conversion efficiency (PCE). It was observed that the PCE rapidly increased with a PEDOT:PSS thickness of up to ∼2,000 rpm and rapidly decreased when the PEDOT:PSS was thicker than ∼2,000 rpm. A PCE of 6.648% was obtained at a specific PEDOT:PSS layer thickness of ∼2,000 rpm, about 41.5% (from 4.698 to 6.648%) higher than the PCE with no PEDOT:PSS layer. In addition, the PCE slightly increased with an LiF layer thickness of up to ∼0.5 nm and rapidly decreased when the LiF layer was thicker than ∼0.5 nm. The maximum PCE was obtained at the LiF layer thickness of ∼0.5 nm. In particular, the maximum values of PCE, Jsc, Voc, and FF were obtained at 6.827%, 15.74 mA/cm2, 0.665 V, and 0.652, respectively. The PCE increased 209.2% (from 2.028 to 6.827%), compared to the LiF layer thickness of ∼5 nm.

This paper proposed UPS system parallel connected in battery and ultracapacitor to compensate instantaneous voltage drop. Ultracapacitor parallel connected with battery compensate instantaneous voltage drop at failure and it`s reduced the voltage regulation of output voltage. We are produced for fast instantaneous voltage drop compensation of ultracapacitor at UPS system and experiments are achieved. Experimental result was verified that the ultracapacitor indicated the fast compensation characteristics and regulation of the output voltage satisfied within 5[%] by using ultracapacitor.

The purpose of this study is localization of safety relief valves for Nuclear Service. The safety relief valve is the important equipment used to protect the pressure vessel, the steam generator and the other pressure facility from overpressure by discharging the operating medium when the pressure of system is reaching the design pressure of the system. We developed design technology used FEM ` CFM about safety relief valve for Nuclear Service according to ASME (or KEPIC) Code and KHNP`s Technical Specification. To prove validity of a design technology, actually, we manufactured and inspected and tested the sample products designed according to a developed technology. The capacity qualification test was achieved according to requirement of ASME(or KEPIC) Code by NBBI and the functional qualification test was achieved according to ASME QME-1 for operating condition in technical specification of KHNP by NLI. Therefore we have to achieve the development of safety relief valves for Nuclear Service with our own technologies.

We have grown an AlIn(Ga)N/GaN heterostructure which is a promising alternative to the AlGaN/GaN heterostructure. The mobility and the carrier concentration of the two-dimensional electron gas (2DEG) formed at the AlIn(Ga)N/GaN heterointerface were strongly dependent on both the growth temperature and pressure. Two optimized growth conditions for the heterostructure with a low sheet resistance less than 300 Ω/sq were obtained by varying the growth temperature and pressure from 750 to 1070 °C and 100 to 300 torr, respectively: (i) AlIn(Ga)N/GaN heterostructure with high 2DEG carrier concentration of 2.4 × 1013 cm−2 with mobility of 1010 cm2 V−1s−1 (grown at 900 °C and 100 torr); (ii) AlIn(Ga)N/GaN heterostructure with high 2DEG mobility of 1910 cm2 V−1s−1 with carrier concentration of 1.13 × 1013 cm−2 (grown at 900 °C and 300 torr). Both structures would be useful for different purpose of device application.

Back-gated MoSe2 thin-film transistors (TFTs) with an Al2O3-capping layer were fabricated, and the device characteristics of the MoSe2 TFTs that are dependent on the Al2O3-capping-layer passivation were investigated. The output drain current was doubled, the fluctuation of the output current was suppressed, and the threshold voltage of the MoSe2 TFTs was negatively shifted with the Al2O3-capping layer. The on/off-current ratio of the MoSe2 TFTs is approximately six decades regardless of the Al2O3-capping layer, but the field-effect mobility was greatly increased from 2.86 cm2/Vs to 10.26 cm2/Vs after the deposition of the Al2O3-capping layer. According to the results of this study, the Al2O3-capping layer can enhance the device characteristics of MoSe2 TFTs.

We investigated the dependence of electron mobility on the thickness of MoS2 nanosheets by fabricating bottom-gate single and few-layer MoS2 thin-film transistors with SiO2 gate dielectrics and Au electrodes. All the fabricated MoS2 transistors showed on/off-current ratio of similar to 10(7) and saturated output characteristics without high-k capping layers. As the MoS2 thickness increased from 1 to 6 layers, the field-effect mobility of the fabricated MoS2 transistors increased from similar to 10 to similar to 18 cm(2)V(-1)s(-1). The increased subthreshold swing of the fabricated transistors with MoS2 thickness suggests that the increase of MoS2 mobility with thickness may be related to the dependence of the contact resistance and the dielectric constant of MoS2 layer on its thickness. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

For applications such as solar cells and displays, transparent single-crystal Si membranes were fabricated on a silicon-on-insulator (SOI) wafer. The SOI wafer included a buried layer of SiO2 and Si3N4 as an etch-stop layer. The etch-stop layer enabled fabrication of transparent single-crystal Si membranes with various thicknesses, and the thinning technology is described. For membranes with thicknesses of 18, 72 and 5000 nm, the respective optical transparent were 96.9%, 93.7% and 9% for R (red, lambda = 660 nm), 96.9%, 91.4% and 1% for G (green, lambda = 525 nm), and 97.0%, 93.2% and 0% for B (blue, lambda = 470 nm). Organic light-emitting diodes (OLEDs) were then fabricated on transparent single-crystal Si membranes with various top Si thicknesses. OLEDs fabricated on 18, 72 and 5000 nm thick membranes and operated at 6 V demonstrated a luminance of 1350, 443 and 27 cd m(-2) at the current densities of 148, 131 and 1.5 mA cm(-2), respectively.

OFDM systems are very sensitive to the phase noise. The phase noise in OFDM has two side effects: common phase error (CPE) and intercarrier interference (ICI). Especially, the rotation of constellation caused by CPE may be fatal in coherent schemes. This paper suggests an equalizer coupled with a phase tracking algorithm to combat frequency selectivity and to correct CPE. Computer simulations prove that CPE can be reduced by the phase tracking loop with low complexity.

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In order to investigate the electrochemical properties of Si electrodes deposited on a roughened current collector (substrate), the electrochemical etching method was applied to a Cu current collector. The surface roughness of a Cu current collector could be controlled with an electrochemical etching time and the roughest surface was obtained at 20 min etched Cu foil. After the etching, a thin Cu2O film was formed on the surface due to high reactivity with air. Amorphous Si films were deposited on flat and rough substrates and their morphologies were considerably affected by those of substrates. A Si electrode with a rough current collector exhibited remarkably improved cycle performance and maintained a discharge capacity over 1200 mA h g−1 even after the 50th cycle. The formation of large cracked Si tiles was caused by the improved adhesion between Si film and Cu substrate.

Electrochemical properties of Si/Ni/Cu film electrodes were investigated with different Ni film thicknesses (50–600 nm) and annealing temperatures (200–500 °C). The morphology of amorphous Si film was considerably affected by surface features of the Ni under-layer. The best cycle performance of 90.2% retention after 70 cycles was obtained from Si/Ni/Cu film with 300 nm thick Ni film and after 400 °C annealing. For the annealed Si/Ni/Cu electrode, the surface morphology (protrusions) and the formation of compounds among Si, Ni and Cu prohibited the volume expansion of Si during the charge–discharge process and enhanced adhesion between films and substrate, respectively.

During pyrolysis of polyimide (PI) thin film, amorphous silicon oxide nanowires (SiO(x)NWs) were produced on a large scale through heat treatment of an Au nanoparticle/PI/Si thin film stack at 1000 °C. It was shown that carbonization of the PI film preceded the nucleation of the SiO(x)NWs. The formation of the SiO(x)NWs was sustained by the oxygen derived from carbonization of the polyimide thin film while Si was provided from the substrate. Au nanoparticles promoted the SiO(x)NW growth by inducing localized melting of the Si substrate and by catalyzing the nanowire growth.

A monolayer of 20 nm sized Fe3C nanoparticles encapsulated by graphite was fabricated by heat treating a polyimide/Fe/polyimide thin-film stack. Transmission electron microscopy and Raman spectroscopy confirmed the graphitization of the polyimide film in the vicinity of the Fe3C particles when annealed above 600 °C. Carbon-encapsulated Fe3C nanoparticles with a narrow size distribution were produced by introducing two-step annealing to initially produce a monolayer of γ-Fe2O3 particles which was converted into carbon-encapsulated Fe3C nanoparticles during the second annealing stage. The thus-produced nanoparticles exhibited a saturation magnetization of 55.4 emu g−1 and coercivity of 360 Oe at room temperature.

Background: There are therapies to lower intracranial pressure (ICP) including head elevation, hyperventilation, diuretics injection, intravenous mannitol, hypothermia, cerebrospinal fluid drainage, and cerebral resection in neurosurgical patients. However in recent reports, hyperventilation followed by mannitol administration may lead to cerebral ischemia. Therefore, we investigated the effect of 0.5 -1.0 g/kg mannitol administration on jugular venous oxygen saturation () and cerebral arterialjugular venous oxygen content difference () at 25-30 mmHg and 35-40 mmHg in patients undergoing neurosurgery. Methods: We studied 17 patients undergoing neurosurgery in the Ajou University Hospital. Anesthesia was induced with fentanyl, midazolam, thiopental, and vecuronium, and maintained with -Air-Isoflorane, a continuous infusion of fentanyl, and vecuronium. Patients were divided into two groups. Group 1 (n = 10) which is 25-30 mmHg and Group 2 (n = 7) which is 35-40 mmHg by controlling ventilator. Measurements of and in following time intervals: I = preinjection of mannitol, II = postinjection 20 minutes of mannitol, III = postinjection 40 minutes of mannitol were obtained for each group. 0.5-1.0 g/kg mannitol was administered intravenously just at duramater opening. Results: Hemodynamics and hematologics were not significantly different among the two groups. of each group are as follows; Group 1; I (70.3 8.1%), II (66.3 6.9%), III (69.1 7.9%) and Group 2; I (78.6 7.4%), II (75.1 8.1%), III (76.0 11.2%). Hyperventilation significantly decreased . was not significantly different but in II was significantly decreased compared with I and III in Group 1 (20% patients). Conclusions: Mannitol produced a change of and during hyperventilation. Therefore, intravenous mannitol during hyperventilation should be given cautiously according to the patients status because it may cause cerebral ischemia in critical patients.