2,083 research outputs found
Awakening in extracorporeal membrane oxygenation as a bridge to lung transplantation
Although the rate of lung transplantation (LTx), the last treatment option for end-stage lung disease, is increasing, some patients waiting for LTx need a bridging strategy for LTx due to the limited number of available donor lungs. For a long time, mechanical ventilation has been employed as a bridge to LTx because the outcome of using extracorporeal membrane oxygenation (ECMO) as a bridging strategy has been poor. However, the outcome after mechanical ventilation as a bridge to LTx was poor compared with that in patients without bridges. With advances in technology and the accumulation of experience, the outcome of ECMO as a bridge to LTx has improved, and the rate of ECMO use as a bridging strategy has increased over time. However, whether the use of ECMO as a bridge to LTx can achieve survival rates similar to those of non-bridged LTx patients remains controversial. In 2010, one center introduced awake ECMO strategy for LTx bridging, and its use as a bridge to LTx has been showing favorable outcomes to date. Awake ECMO has several advantages, such as maintenance of physical activity, spontaneous breathing, avoidance of endotracheal intubation, and reduced use of sedatives and analgesics, but it may cause serious problems. Nonetheless, several studies have shown that awake ECMO performed by a multidisciplinary team is safe. In cases where ECMO or mechanical ventilation is required due to unavoidable exacerbation in patients awaiting LTx, the application of awake ECMO performed by an appropriately trained ECMO multi-disciplinary team can be useful
Retrieval of total precipitable water from Himawari-8 AHI data: A comparison of random forest, extreme gradient boosting, and deep neural network
Total precipitable water (TPW), a column of water vapor content in the atmosphere, provides information on the spatial distribution of moisture. The high-resolution TPW, together with atmospheric stability indices such as convective available potential energy (CAPE), is an effective indicator of severe weather phenomena in the pre-convective atmospheric condition. With the advent of high performing imaging instrument onboard geostationary satellites such as Advanced Himawari Imager (AHI) onboard Himawari-8 of Japan and Advanced Meteorological Imager (AMI) onboard GeoKompsat-2A of Korea, it is expected that unprecedented spatiotemporal resolution data (e.g., AMI plans to provide 2 km resolution data at every 2 min over the northeast part of East Asia) will be provided. To derive TPW from such high-resolution data in a timely fashion, an efficient algorithm is highly required. Here, machine learning approaches-random forest (RF), extreme gradient boosting (XGB), and deep neural network (DNN)-are assessed for the TPW retrieved from AHI over the clear sky in Northeast Asia area. For the training dataset, the nine infrared brightness temperatures (BT) of AHI (BT8 to 16 centered at 6.2, 6.9, 7.3, 8.6, 9.6, 10.4, 11.2, 12.4, and 13.3 ??m, respectively), six dual channel differences and observation conditions such as time, latitude, longitude, and satellite zenith angle for two years (September 2016 to August 2018) are used. The corresponding TPW is prepared by integrating the water vapor profiles from InterimEuropean Centre for Medium-Range Weather Forecasts Re-Analysis data (ERA-Interim). The algorithm performances are assessed using the ERA-Interim and radiosonde observations (RAOB) as the reference data. The results show that the DNN model performs better than RF and XGB with a correlation coefficient of 0.96, a mean bias of 0.90 mm, and a root mean square error (RMSE) of 4.65 mm when compared to the ERA-Interim. Similarly, DNN results in a correlation coefficient of 0.95, a mean bias of 1.25 mm, and an RMSE of 5.03 mm when compared to RAOB. Contributing variables to retrieve the TPW in each model and the spatial and temporal analysis of the retrieved TPW are carefully examined and discussed. ?? 2019 by the authors
Design optimization of coil gun to improve muzzle velocity
Recently, a coil gun was brought to the attention of engineering community as electromagnetic alternative to the chemical launchers. Various studies were performed on coil gun systems focused on achieving the high muzzle velocity in military applications and for satellite launching. Most of these studies focused on improvement of muzzle velocity via increase in the size of the coil gun. Present paper describes the process of design optimization where the size of the coli gun system is restricted. The design of experiment approach utilizes the orthogonal array table that reduces the required number of experiments. The design of experiment is carried out with a commercial PIAnO tool, where the finite element analysis is performed at each experimental point. Then, Kriging model is created to achieve accurate approximation in problems of many design variables or strongly nonlinear model. The coil gun is optimally designed using an evolutionary algorithm (EA) as optimization technique. In order to verify the improvement of muzzle velocity by optimal design, the prototypes of coil gun system are manufactured and the experiments to launch the projectile are performed
(7-Dimethylamino-1-hydroxy-3-naphthyl)(morpholino)methanone
In the title compound, C17H20N2O3, the morpholine ring is in a slightly distorted chair form. The crystal structure is stabilized by an intermolecular O—H⋯O hydrogen bond between the H atom of the hydroxyl group and the O atom of a neighbouring carbonyl group. A weak intermolecular C—H⋯π interaction is also present
Squeezing Limit of the Josephson Ring Modulator as a Non-Degenerate Parametric Amplifier
Two-mode squeezed vacuum states are a crucial component of quantum
technologies. In the microwave domain, they can be produced by Josephson ring
modulator which acts as a three-wave mixing non-degenerate parametric
amplifier. Here, we solve the master equation of three bosonic modes describing
the Josephson ring modulator with a novel numerical method to compute squeezing
of output fields and gain at low signal power. We show that the third-order
interaction from the three-wave mixing process intrinsically limits squeezing
and reduces gain. Since our results are related to other general cavity-based
three-wave mixing processes, these imply that any non-degenerate parametric
amplifier will have an intrinsic squeezing limit in the output fields.Comment: 6+6 pages, 4 figure
The effects of laparoscopic assisted total gastrectomy on surgical outcomes in the treatment of gastric cancer
Bound for Gaussian-state Quantum illumination using direct photon measurement
We present bound for quantum illumination with Gaussian state when using
on-off detector or photon number resolving detector, where its performance is
evaluated with signal-to-noise ratio. First, in the case of coincidence
counting, the best performance is given by two-mode squeezed vacuum (TMSV)
state which outperforms coherent state and classically correlated thermal (CCT)
state. However coherent state can beat the TMSV state with increasing signal
mean photon number when using the on-off detector. Second, the performance is
enhanced by taking Fisher information approach of all counting probabilities
including non-detection events. In the Fisher information approach, the TMSV
state still presents the best performance but the CCT state can beat the TMSV
state with increasing signal mean photon number when using the on-off detector.
We also show that displaced squeezed state exhibits the best performance in the
single-mode Gaussian state.Comment: 5 pages, 2 figures, comments welcom
Comparison of Surgical Outcomes in Thoracolumbar Fractures Operated with Posterior Constructs Having Varying Fixation Length with Selective Anterior Fusion
PURPOSE: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate.
MATERIALS AND METHODS: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire.
RESULTS: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter.
CONCLUSION: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.ope
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