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Various volatile anesthetics and ischemic preconditioning (IP) have been demonstrated to exert protective effect against ischemia/reperfusion (I/R) injury in liver. We aimed to determine whether application of IP under isoflurane and sevoflurane anesthesia would confer protection against hepatic I/R injury in rats.Thirty-eight rats weighing 270 to 300 grams were randomly divided into 2 groups: isoflurane (1.5%) and sevoflurane (2.5%) anesthesia groups. Each group was subdivided into sham (n = 3), non-IP (n = 8; 45 minutes of hepatic ischemia), and IP (n = 8, IP consisting of 10-minute ischemia plus 15-minute reperfusion before prolonged ischemia) groups. The degree of hepatic injury and expressions of B-cell lymphoma 2 (Bcl-2) and caspase 3 were compared at 2 hours after reperfusion.Hepatic ischemia induced significant degree of I/R injuries in both isoflurane and sevoflurane non-IP groups. In both anesthetic groups, introduction of IP dramatically attenuated I/R injuries as marked by significantly lower aspartate aminotransferase and aminotransferase levels and better histologic grades compared with corresponding non-IP groups. There were 2.3- and 1.7-fold increases in Bcl-2 mRNA levels in isoflurane and sevoflurane IP groups, respectively, compared with corresponding non-IP groups (both P .05). Caspase 3 level was significantly high in the isoflurane non-IP group compared with the sham group; however, there were no differences among the sevoflurane groups.The degree of hepatic I/R injury was significantly high in both isoflurane and sevoflurane groups in rats. However, application of IP significantly protected against I/R injury in both volatile anesthetic groups to similar degrees, and upregulation of Bcl-2 might be an important mechanism.

In order to understand repetitive convective transport and its flow physics over the flat tip of a turbine blade, high-spatial resolution measurements of thermal load and aerodynamic loss are performed in a large-scale cascade. The thermal load distributions measured with the naphthalene sublimation technique show that for two tip gaps of h/s = 1.0% and 2.0%, there is a repetitive change of thermal load upstream of the mid-chord, and wider tip gap makes thermal load change more severe but less repetitive. The mean distance between the neighboring peaks of thermal load in the direction normal to local flow for h/s = 2.0% is twice the one for h/s = 1.0%. Present total pressure measurements show that in the area of repetitive thermal load change for h/s = 2.0%, there exists a distinct repetitive loss change only near the tip surface. A qualitative flow model in the area of repetitive change is proposed for h/s = 2.0%. According to the flow model, the separation bubble undergoes a wave-like repetitive change in its thickness and length. Just behind the ridge of the wave-like separation bubble, low thermal load coexists with high loss, whereas just behind its valley, high thermal load coexists with low loss.

Background The tip of the tracheal tube should lie at the mid-tracheal level after tracheal intubation in paediatric patients. Auscultation does not guarantee optimal positioning of the tracheal tube. We compared auscultation and the ultrasound-guided lung sliding sign to confirm optimal positioning of the tracheal tube in paediatric patients. Methods We studied 74 paediatric patients aged 0–24 months of ASA physical status 1–3 who were scheduled for elective surgery under general anaesthesia. All were randomly assigned to one of two groups: depth of tracheal tube confirmed by auscultation (Group A) or using the ultrasound-guided lung sliding sign (Group S). Results Optimal positioning of the tracheal tube was observed in 32 of 37 (87%) subjects in Group S and 24 of 37 (65%) subjects in Group A (difference in proportion, 22%; 95% confidence interval, 2–39%; P=0.030). Optimal depth correlated with patient height (adjusted coefficient=0.888, P Conclusions In paediatric patients younger than 24 months, use of the ultrasound-guided lung sliding sign was more accurate than auscultation for optimal positioning of the tracheal tube. Clinical trial registration KCT 0003015.

Inversion layer technique can increase the centre frequency (f 0) and the −6 dB bandwidth of the ultrasound transducer without reducing thickness of active material. However, it suffers from the reduced −6 dB bandwidth when the centre frequency is increased more than 1.5f 0. A modified inversion technique is proposed and applied it to high-frequency intravascular ultrasound (IVUS) transducer. The performance was computationally verified by using finite element method (FEM) simulation. The proposed IVUS transducer consists of two sub-elements with each aperture size of 0.6 × 0.6 mm, and each sub-element has different types of inversion layer using PMN-PT and PZT-5H. The initial thickness of overall active material was designed for 40 MHz centre frequency and the FEM simulation showed that the centre frequency was increased by about 1.8f 0 maintaining the −6 dB fractional bandwidth compared with the conventional transducer.

Reliability evaluation approaches to equipment systems consisting of hundreds of parts and dozens of modules have limitations with respect to environmental testing, life testing, and accelerated life testing. Equipment systems cannot be tested with a statistically verifiable sample number. Therefore, screening methods used by manufacturers involve short operational tests after production; failures occurring in the field are dealt with after delivery. The frequency of maintenance checks is closely related to the company's reputation and life cycle costs (LCCs). The aim of this study is to investigate ways to reduce maintenance cost and high LCCs by the company's reliability related processor. First, we classified equipment industries into three categories: machine processing, semiconductor processing, and inspection. Then, we investigated user requirements for equipment systems. We found that there were different demands for each industry. For equipment used in the machine processing industry, capability (productivity, adaptability, flexibility, and precision) and reliability (reliability of drive system, bearing failure rate) are considered (Jo-Peng et al., 2010 [ 1 ]). Equipment used in the semiconductor process is required to be employed for immediate use; further, they are required to be highly accurate. Inspection equipment is usually manufactured by small companies; therefore, they have problems associated with quality and initial failures. Next, we proposed the practical quality, reliability, and maintenance (QRM) processes to reduce high LCCs for four years. Before implementing the processes, we developed and applied an evaluation index that evaluated the quality management status, reliability, and maintenance aspects of the company. The index was designed by the behaviorally anchored rating scale (BARS) technique, which is a quantitative calculation method (Martin-Raugh et al., 2016). The results showed that companies could reduce their LCCs and improve their reliability.

Significant neutron peak broadening was observed in situ underneath the tool of friction stir processing (FSP) in 6061-T6 aluminum alloy. Such broadening was correlated to the dislocation density and subgrain size by using peak profile analysis methods. The high dislocation density of about 1.3×10 15 m −2 underneath the FSP tool sharply decreases to 1.0×10 14 m −2 outside the tool. The quantitative determination is consistent with the high-resolution x-ray and TEM results.

The objective of this study was to determine the effect of deoxynivalenol (DON) on in vitro rumen fermentation by assessing pH, ammonia-N, total gas, volatile fatty acid (VFA) production, and DON degradation under the context of two different carbon sources (corn starch or cellulose). Fifty millilitre of ruminal fluid:buffer (1:1) was incubated for up to 6 h with four possible treatments: corn starch 1.5 g, corn starch 1.5 g + DON at 40 mg/kg dry matter (DM), cellulose 1.5 g, and cellulose 1.5 g + DON at 40 mg/kg DM. Our results indicate that carbon source appears to markedly influence all rumen fermentative parameters (P

MWNT/nylon 6, 6 composite nanofibers were fabricated using an electrospinning method, and the electrical properties were examined as a function of the filler concentration. Initially, the pristine, purified MWNTs were treated with a 3:1 mixture of concentrated H2SO4/HNO3 to introduce carboxyl groups onto the MWNT surface. The carboxylated MWNTs were then treated with thionyl chloride and an ethylenediamine solution for amide functionalization. FT-IR spectroscopy was used to examine the functionalization of the MWNTs. Nylon 6, 6 is readily soluble in formic acid. Therefore, the amide functionalized MWNTs were dispersed in formic acid. The solution remained stable and uniform for more than 40 h. –NH2 termination of the MWNTs improved the dispersion stability of the MWNTs in formic acid. The MWNTs-suspended in a solution of nylon 6, 6 in formic acid was electrospun to obtain the nanofibers. The electrical properties of the nanofibers were examined as a function of the filler concentration. The results showed that the I–V properties of the nanofiber sheet improved with increasing filler concentration.

Development of practical SWCNT-based chemical sensors is impeded because of difficulties in controlling both orientation/morphology in a MEMs-based sensor platform and the purity of nano-material. Methods to purify CNTs, prior to and following device fabrication are described. More critically, methodology to control the physical morphology of SWCNT on a MEMs platform has been applied for sensor applications.

The quality of focusing in high-frequency ultrasound imaging is significantly affected by the length of the depth of field (DOF). A dual-concentric transducer combined with a phase-apodisation scheme is presented to achieve the extended DOF maintaining signal-to-noise ratio. As a preliminary study, computational simulation by using a Field-II program is conducted to demonstrate the feasibility. A dual-concentric transducer is composed of a disc- and a ring-type element with confocal apertures. When two input signals with 0° and 180° phases are simultaneously applied to the inner and outer elements, a bifocal-zone is generated in the axial direction. The overall − 6 dB DOF is 40% longer compared with a single element transducer. Thus, the proposed scheme can be a potential approach to increase the DOF for high-frequency ultrasound imaging.

Real-time ultrasound imaging during high-intensity focused ultrasound (HIFU) surgery allows for tracking tissue movement and monitoring feedback from a treated target. However, the reflected HIFU interference signals deteriorate the quality of imaging signals received by an imaging transducer during simultaneous therapy and imaging. The purpose of this Letter is to demonstrate that those HIFU interference signals can be significantly reduced in the brightness-mode image by using a coded excitation scheme with adaptive notch filtering. A prototype integrated HIFU/imaging transducer was used to experimentally demonstrate the performance of the proposed method.

In this study, the effects of electrical aging on emission stability of screen-printed carbon nanotube(CNT) emitter is investigated. Results show that stable and uniform emission currents from CNT emitter are obtained during the multiple field emission cycling. During the initial stage of electrical aging, an emission current fluctuation is observed and is gradually reduced and electron emission stabilized as time passes.

Introduction Living related liver transplantation (LRLT) has been performed since 1994 in Korea; more than 600 donors have contributed to our successful LRLT program for 10 years. Although the decision to donate is difficult and the donors need a formal psychosocial assessment, no system has been available to us for the assessment. This survey was performed as a presurveillance for the development of a psychosocial assessment protocol. Methods A survey questionnaire included 31 questions on general and medical characteristics, factors, and processes related to the decision for donation. Donors of partial livers at least 6 months ago during the period from December 1994 to August 2003 and whose address could be confirmed by telephone were enrolled in the study. Results A questionnaire was sent by mail to 441 contactable donors of whom 209 (47.4%) responded. Male-to-female ratio was 2:1 and mean age was 32.8 years (range: 16 to 60 years). The number of spousal donors was 120 (57.4%) and 164 (78.5%) donors were employed at the time of donation. Protestants, Buddhists, and Catholics were 29.2%, 19.1%, and 14.8%, respectively. Parents were the most common recipients (33.0%), followed by siblings (17.2%), extended family members (17.2%), and children (15.8%); one hundred eighty nine (90.4%) donors had decided by themselves, the major reason for donation in 192 (91.9%) donors was “to save the lives of family members and relatives.” The first person who suggested donation was the donor (64.1%), followed by family members (23.9%) or the attending physicians (8.6%). Although 70.8% of donors answered that they were not hesitant to donate at the time of decision, 44.5% were uneasy at the possibility of being unable to sustain a normal life after donation, at their lack of knowledge on organ donation, and about the pain and fear of surgery. Family members and relatives (53.3%), medical personnel (46.7%), and previous donors (35.4%) were the preferable counselors compared to transplantation institutions and clergymen. The large majority (80.8%) of donors would encourage others to donate. Conclusions Although the decision to donate was made by the donors themselves in most cases and they appeared firm and determined about their decision, a significant number of donors felt uneasy about possible complications of organ donation and effects on their lives after donation. A precise and formal psychosocial assessment protocol is needed to support and secure their decision before and after donation.

This paper describes a method for overcoming motion artifacts in synthetic aperture imaging. The method is based on a computer simulation study on the influence of target motion on synthetic aperture techniques. A region-based motion compensation approach is used in which only the axial motion is estimated and compensated for a given region of interest under the assumption that the whole ROI moves uniformly. The estimated axial motion is calculated with a crosscorrelation method at the point where the focused signal has the maximum energy within the ROI. We also present a method for estimating axial motion using the autocorrelation method that is widely used to estimate average Doppler frequency. Both computer simulations and in vivo experiments show that the proposed crosscorrelation-based method can greatly improve the spatial resolution and SNR of ultrasound imaging by implementing SA techniques for two-way dynamic focusing without motion artifacts. In addition, the autocorrelation-based motion compensation method provides almost the same results as the crosscorrelation-based method, but with a dramatically reduced computational complexity.

Introduction: We report the results of our prospective single arm study performed to evaluate the efficacy of Imatinib mesylate (IMT) dose-escalation therapy and the influence of BCR/ABL mutational status on the treatment outcome. Methods: Patients with chronic phase(CP) chronic myelogenous leukemia (CML) who had not achieved a complete hematologic response (CHR) after 3 months, a major cytogenetic response (MCyR) after 6 months, nor a complete cytogenetic response (CCyR) after 6-12 months of standard IMT therapy (400mg per day) were included. Patients in accelerated phase (AP) or blast crisis (BC) who had failed to achieve CHR after 3 months of IMT (400 or 600mg per day) were also eligible. 600mg of IMT had been administered for patients with CP CML per day, and 600mg or 800mg for AP or BC CML for at least 12 months. For each patient, BCR/ABL gene mutation test was performed on 6 loci. Cytogenetic response (CyR) was evaluated with the percentage of bcr/abl positive cells in bone marrow aspirate by means of FISH per 6 months. Molecular responses (MR) were assessed per 3 months with a logarithmic decrease in BCR-ABL/ABL gene ratio (BA/A) of peripheral blood or bone marrow aspirate from a standardized median value of BA/A in 56 patients with newly diagnosed CML. Results: 77 patients were enrolled and 61 patients were assessable for the evaluation of MR. The median age was 50 years old (range: 20-70). Stages at the time of the enrollment were CP for 56, AP for 4, BC for 1 patient(s). The median time from the initiation of IMT therapy to dose-up was 20 months (range: 0-62). BCR/ABL gene mutational status could be obtained in 24 patients (wild:mutant=20:4). The median follow-up was 19.9 months (range: 6.5-24.3). For 34 patients whose 6th-month CyR is available, MCyR rate (MCyRR) was 26.5% and CCyR rate (CCyRR) was 23.5%. The 12th-month MCyRR was 61.1% and CCyRR was 50.0%. Patients with wild type showed a MCyRR of 20% and a CCyRR of 15% on the 12th month after dose-up, whereas no patient with mutant type showed a CCyR or a MCyR. CMR rate and MMR rate on the 12th-month were 16.7% and 26.7%. Among 20 patients with wild type, one patient achieved a 6th-month CMR, 2 patients MMR’s, whereas no patient with mutant type could achieve a MMR during the entire treatment period. Hematologic and non-hematologic toxicities were tolerable. Conclusion: IMT dose-escalation could induce quite a number of durable CyR’s and MR’s without any serious toxicity in patients who had failed to achieve either a CHR or a CyR with a standard IMT therapy.

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