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This study aims to enhance second language (L2) learners' motivation and facilitate successful L2 learning by using motivational languaging, an intervention that encourages learners to reflect on, and externalize, their L2-speaking, competent future self-concepts by writing or speaking about them. Two types of effective languaging activities were developed: individual and group writing. Participants were 264 Grade 10 high school students, divided into three groups: one control group and two experimental groups. Using activity workbooks, the first experimental group engaged in 'individual writing' guided by a series of questions in their workbooks (e.g. reasons for learning English and their ideal images of using English). The second experimental group carried out 'group writing', including group discussions and writing of group members' opinions. The activities were conducted in the participants' first language, Korean, for 30–40 minutes once a week for six weeks. The results indicated, in the two experimental groups, that the participants' L2 learning motivation was enhanced, including the ideal L2 self. When observing the changes in the influence of motivation on motivated L2 learning behavior and English proficiency, meaningful increases were only found in the individual writing group, with the ideal L2 self showing more powerful impact on the two criterion measures after the activities. [ABSTRACT FROM AUTHOR]

To determine if the prevalence and severity of restless legs syndrome (RLS) varies with apnea severity and analyze differences between the sexes in terms of comorbid RLS with symptoms of depression, insomnia, and daytime sleepiness in patients with obstructive sleep apnea (OSA). Symptoms of depression, insomnia, and daytime sleepiness were defined as Patient Health Questionnaire–9 score ≥10, Insomnia Severity Index score ≥15, and Epworth Sleepiness Scale score ≥11. Multivariate logistic and linear regression analyses were conducted. In 707 adults with OSA (85.1% males), 16.1% (n = 114) had comorbid RLS. The prevalence of RLS was markedly lower in those with moderate and severe OSA than in those with mild OSA. Similarly, the odds of RLS significantly decreased with increasing apnea-hypopnea index. After controlling for age and sex, in patients with comorbid RLS, the International RLS Study Group Rating Scale scores were negatively correlated with apnea-hypopnea index and a nadir peripheral oxygen saturation during sleep. The presence of RLS was more likely to be associated with symptoms of depression, insomnia, and daytime sleepiness after controlling for confounding variables, but only in men. RLS is frequently noted in combination with OSA, with a female preponderance. The severities of OSA and RLS may be negatively associated. In patients with OSA, sex-related differences in terms of comorbid RLS with symptoms of depression, insomnia, and daytime sleepiness warrant further investigations. • The RLS prevalence was 16.1% of patients with OSA, with female preponderance. • OSA severity was negatively correlated with the prevalence and severity of RLS. • RLS was more likely to be associated with symptoms of depression, insomnia, and daytime sleepiness. • However, these associations were observed only in males and not in females. [ABSTRACT FROM AUTHOR]

Developing thin, highly stretchable coatings that inhibit the undesirable adhesion of biological substances on soft and high‐water‐content biomaterial surfaces is an area of significant interest. In this study, a stretchable antifouling coating named lubricant‐infused poly(1,3,5,7‐tetramethyl‐1,3,5,7‐tetravinyl cyclotetrasiloxane) (V4D4) is introduced interface with perfluoropolymer (L‐VIP). The stretchable adhesive‐perfluoropolymer bilayer comprises stretchable adhesive polymer (V4D4) and perfluoropolymer (1H,1H,2H,2H‐perfluorooctyl methacrylate (FOMA)). The bilayer exhibits a strong affinity with the lubricant, imparting exceptional antifouling and slippery properties. L‐VIP coating displays superior fouling resistance against plasma proteins related to foreign body reactions (FBR) and biofilm‐forming bacteria. The coating exhibits impressive elastic limits exceeding 200% strain and exceptional stability under repeated cyclic stretching (> 2000 cycles at 150% strain) while maintaining its antifouling properties. Furthermore, the coating presents dielectric performance under accelerated aging conditions at a temperature of 70° and constant voltage stress of 10 V s−1 for over 50 days. To assess the biocompatibility of the L‐VIP coating, a series of in vitro and in vivo experiments are conducted, confirming its non‐toxicity for biomedical applications. It is expected that the stretchable L‐VIP coating will enhance medical devices' longevity and help prevent bacterial infections, the formation of biofilms, and the nonspecific adherence of biological substances after implantation. [ABSTRACT FROM AUTHOR]

This study was conducted to confirm the Cs-137 and Sr-90 adsorption properties of illite. In the experimental method, illite was added to Cs-137 and Sr-90 solutions and stirred. And Following the completion of the adsorption reaction, the solid/liquid phase was separated using a centrifuge, and the adsorption rate was calculated by measuring the radioactivity concentration of the separated liquid phase using a gamma nuclide analyzer, Liquid Scintillation Count (LSC). As a result of the experiment, after reacting for 30 min, 94% of Cs-137 was adsorbed. And 84.26% of Sr-90 was adsorbed. [ABSTRACT FROM AUTHOR]

Nymphoides peltata has been used as a medicinal herb in traditional medicines to treat strangury, polyuria, and swelling. The phytochemical investigation of the MeOH extract of N. peltata roots led to the isolation of three iridoid glycosides and three coumarin glycoside derivatives, which were characterized as menthiafolin (1), threoninosecologanin (2), callicoside C (3), and scopolin (4), as well as two undescribed peltatamarins A (5) and B (6). The chemical structures of the undescribed compounds were determined by analyzing their 1 dimensional (D) and 2D nuclear magnetic resonance (NMR) spectra and using high-resolution (HR)-electrospray ionization mass spectroscopy (ESI-MS), along with the chemical reaction of acid hydrolysis. The wound healing activities of the isolated compounds 1–6 were evaluated using a HaCaT cell scratch test. Among the isolates, scopolin (4) and peltatamarin A (5) promoted HaCaT cell migration over scratch wounds, and compound 5 was the most effective. Furthermore, compound 5 significantly promoted cell migration without adversely affecting cell proliferation, even when treated at a high dose (100 μM). Our results demonstrate that peltatamarin A (5), isolated from N. peltata roots, has the potential for wound healing effects. [ABSTRACT FROM AUTHOR]

Lipid biosynthesis is recently studied its functions in a range of cellular physiology including differentiation and regeneration. However, it still remains to be elucidated in its precise function. To reveal this, we evaluated the roles of lysophosphatidic acid (LPA) signaling in alveolar bone formation using the LPA type 2 receptor (LPAR2) antagonist AMG‐35 (Amgen Compound 35) using tooth loss without periodontal disease model which would be caused by trauma and usually requires a dental implant to restore masticatory function. In this study, in vitro cell culture experiments in osteoblasts and periodontal ligament fibroblasts revealed cell type‐specific responses, with AMG‐35 modulating osteogenic differentiation in osteoblasts in vitro. To confirm the in vivo results, we employed a mouse model of tooth loss without periodontal disease. Five to 10 days after tooth extraction, AMG‐35 facilitated bone formation in the tooth root socket as measured by immunohistochemistry for differentiation markers KI67, Osteocalcin, Periostin, RUNX2, transforming growth factor beta 1 (TGF‐β1) and SMAD2/3. The increased expression and the localization of these proteins suggest that AMG‐35 elicits osteoblast differentiation through TGF‐β1 and SMAD2/3 signaling. These results indicate that LPAR2/TGF‐β1/SMAD2/3 represents a new signaling pathway in alveolar bone formation and that local application of AMG‐35 in traumatic tooth loss can be used to facilitate bone regeneration and healing for further clinical treatment. [ABSTRACT FROM AUTHOR]

Hydrogels are used in wound dressings because of their tissue‐like softness and biocompatibility. However, the clinical translation of hydrogels remains challenging because of their long‐term stability, water swellability, and poor tissue adhesiveness. Here, tannic acid (TA) is introduced into a double network (DN) hydrogel consisting of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) to realize a tough, self‐healable, nonswellable, conformally tissue‐adhesive, hemostatic, and antibacterial hydrogel. The TA within the DN hydrogel forms a dynamic network, enabling rapid self‐healing (within 5 min) and offering effective energy dissipation for toughness and viscoelasticity. Furthermore, the hydrophobic moieties of TA provide a water‐shielding effect, rendering the hydrogel nonswellable. A simple chemical modification to the hydrogel further strengthens its interfacial adhesion with tissues (shear strength of ≈31 kPa). Interestingly, the TA also can serve as an effective hemostatic (blood‐clotting index of 58.40 ± 1.5) and antibacterial component, which are required for a successful wound dressing. The antibacterial effects of the hydrogel are tested against Escherichia coli and Staphylococcus aureus. Finally, the hydrogel is prepared in patch form and applied to a mouse model to test in vivo biocompatibility and hemostatic performances. [ABSTRACT FROM AUTHOR]

In this study, a Ru-doped Ni pellet-type catalyst was prepared to produce hydrogen via steam methane reforming (SMR). A small amount of Ru addition on the Ni catalyst improved Ni dispersion, thus affording a higher catalytic activity than that of the Ni catalyst. During the daily startup and shutdown (DSS) operations, the CH4 conversion of Ni catalysts significantly decreased because of Ni metal oxidation to NiAl2O4, which is not reduced completely at 700 °C. Conversely, the oxidized Ni species in the Ru–Ni catalyst can be reduced under SMR conditions because of H2 spillover from the surface of Ru onto the surface of Ni. Consequently, the addition of a small quantity of Ru to the Ni catalyst can improve the catalytic activity and stability during the DSS operation. [ABSTRACT FROM AUTHOR]

A series of 1,4‐bis(N‐alkylpyrrolidinium)butane salts combined with Br−, I−, PF6−, and Tf2N− anions were newly designed and synthesized. In nonpolar CDCl3 solution, the axial and equatorial proton peaks of the bis‐pyrrolidinium cation ring are distinguished in 1H NMR. Also, the strengths of ion paring could be estimated from the 1H NMR chemical shift changes of the bridge and pyrrolidinium proton peaks. 1,4‐Bis(N‐hepthylpyrrolidinium)butane I− is an organic ionic plastic crystal showing the lowest fusion entropy value (ΔSf = 3.4 J K·mol−1). Softer crystalline morphologies were found by polarized optical microscope images at plastic crystal phase of each sample and the results were corresponding to differential scanning calorimetry results. 1,4‐Bis(N‐ethylpyrrolidinium)butane Tf2N− showed the softest crystal phase. Ionic conductivity changes and electrochemical stabilities of the bis‐pyrrolidinium PF6− and Tf2N− salts were also measured, and they were stable up to 4.3 V (vs. Li/Li+) and expected to be applied as an electrolyte component. [ABSTRACT FROM AUTHOR]

Energy and power demands for military operations continue to rise as autonomous air, land, and sea platforms are developed and deployed with increasingly energetic weapon systems. The primary limiting capability hindering full integration of such systems is the need to effectively and efficiently manage, generate, and transmit energy across the battlefield. Energy efficiency is primarily dictated by the number of dissimilar energy conversion processes in the system. After combustion, a Compression Ignition (CI) engine must periodically continue to inject fuel to produce mechanical energy, simultaneously generating thermal, acoustic, and fluid energy (in the form of unburnt hydrocarbons, engine coolant, and engine oil). In this paper, we present multiple sets of Shallow Artificial Neural Networks (SANNs), Convolutional Neural Network (CNNs), and K-th Nearest Neighbor (KNN) classifiers, capable of approximating the in-cylinder conditions and informing future optimization and control efforts. The neural networks provide outstanding predictive capabilities of the variables of interest and improve understanding of the energy and power management of a CI engine, leading to improved awareness, efficiency, and resilience at the device and system level. [ABSTRACT FROM AUTHOR]

We determined whether the severity of sleep apnea increases the risk of mortality in patients with multiple system atrophy (MSA) with and without stridor. MethodsThis retrospective study included patients who underwent polysomnography within one year after diagnosis of probable MSA. Stridor, sleep apnea, and arousal from sleep were determined using full-night polysomnography. Disease severity was measured using the Unified MSA Rating Scale (UMSARS). Survival data were collected and analyzed using Cox regression analysis. Sixty-four patients with MSA were included. During a median follow-up of 34.5 months, 49 (76.6 %) patients died. Stridor was present in 56.3 % of patients. Patients with stridor had more severe sleep apnea and shorter sleep time than those without, but the hazard ratio (HR) for death did not differ between patients with and without stridor. Among patients without stridor, apnea-hypopnea index ≥30/h (HR, 6.850; 95 % confidence interval [CI], 1.983–23.664; p = 0.002) and a score of UMSARS I + II (HR, 1.080; 95 % CI, 1.040–1.121; p < 0.001) were independently associated with death. In contrast, among patients with stridor, frequent arousals from sleep (HR, 0.254; 95 % CI, 0.089–0.729; p = 0.011) were a significant factor associated with longer survival, while MSA-cerebellar type tended to be associated with poor survival (HR, 2.195; 95 % CI, 0.941–5.120; p = 0.069). The severity of sleep apnea might be a significant predictor of shorter survival in MSA patients without stridor, whereas frequent arousals from sleep might be a significant predictor for longer survival in MSA patients with stridor. • Nocturnal stridor was present in 56.3 % of patients with multiple system atrophy (MSA). • The risk for mortality did not differ between MSA patients with and without stridor. • Severity of sleep apnea was related to shorter survival in patients without stridor. • Frequent arousals from sleep were associated with longer survival in patients with stridor. [ABSTRACT FROM AUTHOR]

To improve the performance of a meso-scale thermophotovoltaic (TPV) power device, the internal heat recirculation using porous media (PM) is applied to a TPV combustor with external heat recovery and multiple injectors, which was developed in the previous study of this laboratory. The combustion performance of the PM-inserted combustor is evaluated, and then the TPV performance is demonstrated for practical applications, using the meso-scale TPV device that consists of the PM combustor with various emitters, a module of 96 gallium antimonide cells and a cooling device and was not considered in the previous study. The present TPV device adopting a MgO emitter could be used in meso-scale power generation systems, particularly for military applications, if the device size and weight and the noise level are considered along with the TPV performance (i.e., the maximum output power of 18.9 W) that is evaluated to be suitable for the meso-scale power device. [ABSTRACT FROM AUTHOR]

Uveal effusion is a rare disease that is characterized by exudative detachment of the ciliary body and choroid. Herein, we report a rare case of uveal effusion associated with viral encephalitis, which resolved following the treatment of the viral encephalitis and administration of corticosteroids. A 67-year-old man who was hospitalized for viral encephalitis was referred to our clinic. He had been treated for herpes zoster ophthalmicus in his left eye 3 weeks previously. Choroidal detachment and uveal effusion between the ciliary body and sclera were observed. He was prescribed oral and topical steroids and cycloplegics to treat uveal effusion, and an antiviral agent (Acyclovir) to treat viral encephalitis. After 4 weeks, the choroidal detachment resolved completely. Uveal effusion syndrome can develop in association with viral encephalitis and be treated successfully with oral and topical steroids; we suggest that medical treatment should be attempted prior to surgery. ADEM: Acute disseminated encephalomyelitis; BCVA: Best corrected visual acuity; CSF: Cerebrospinal fluid; CT: Computed tomography; MRI: Magnetic resonance imaging; WBC: White blood cell [ABSTRACT FROM AUTHOR]

To evaluate multifocal evanescent white dot syndrome (MEWDS) patients with and without overlapping multifocal choroiditis (MFC). Thirty-four patients diagnosed between November 2008 and August 2018 at 2 hospitals were retrospectively reviewed. Multimodal imaging including optical coherence tomography angiography (OCTA) was assessed. Twenty-seven (79%) patients were women (overall mean age, 30 years). Five developed MFC lesions in the affected eyes, and one developed MFC in the unaffected fellow eye. Another developed combined MEWDS and MFC in the fellow eye during follow-up. Eyes with MFC had thicker choroids (316.5 and 197.3 µm, respectively; P =.001) at presentation, which became thinner after resolution (P =.043). Those with subfoveal MFC had poor visual prognosis (P =.019). Areas of suspected choriocapillaris flow deficit were identified on OCTA. Some MEWDS patients may develop overlapping MFC in the same or fellow eyes, presenting with increased choroidal thickness which decreased after resolution. [ABSTRACT FROM AUTHOR]

In this study, real-time predictive control and optimization model based on an ANN (artificial neural network) was developed to evaluate the cooling energy saving performance of the optimized control of CndWT (condenser water temperature). For this purpose, the difference in TCEC (total cooling energy consumption) between the conventional control strategy when the CndWT produced by the cooling tower is fixed and the optimized control strategy when real-time control of the CndWT through the optimal ANN model is applied was compared and analyzed. For the modeling of the building to be simulated, the co-simulation of EnergyPlus and MATLAB was built through the middleware Building Controls Virtual Test Bed. For the prediction of TCEC, an ANN model was developed through MATLAB's neural network toolbox. The model accuracy of the ANN was examined through Cv(RMSE) index and as a result, Cv(RMSE) of the optimized ANN model turned out to be approximately 25 %. More importantly, the predictive control technique was able to save TCEC by 5.6 % compared to the conventional control method constantly fixing CndWT set-point to 30 °C. These results showed that the CndWT needs to be dynamically controlled using artificial intelligence technique such as ANN model and that significant energy savings were achievable compared to the conventional fixed control. [ABSTRACT FROM AUTHOR]

Most existing electrocardiogram (ECG) feature extraction methods rely on rule-based approaches. It is difficult to manually define all ECG features. We propose an unsupervised feature learning method using a convolutional variational autoencoder (CVAE) that can extract ECG features with unlabeled data. We used 596,000 ECG samples from 1,278 patients archived in biosignal databases from intensive care units to train the CVAE. Three external datasets were used for feature validation using two approaches. First, we explored the features without an additional training process. Clustering, latent space exploration, and anomaly detection were conducted. We confirmed that CVAE features reflected the various types of ECG rhythms. Second, we applied CVAE features to new tasks as input data and CVAE weights to weight initialization for different models for transfer learning for the classification of 12 types of arrhythmias. The f1-score for arrhythmia classification with extreme gradient boosting was 0.86 using CVAE features only. The f1-score of the model in which weights were initialized with the CVAE encoder was 5% better than that obtained with random initialization. Unsupervised feature learning with CVAE can extract the characteristics of various types of ECGs and can be an alternative to the feature extraction method for ECGs. [ABSTRACT FROM AUTHOR]

We aimed to analyze the effects and explore the molecular mechanisms of a natural herb mixture extract (NME) on osteoblasts during differentiation in human bone marrow-derived mesenchymal stem cells (hBMSCs). We tried to confirm the regulation of osteogenic differentiation during NME treatment. Alkaline phosphatase assay and Alizarin red S staining were performed to evaluate the regulation of osteogenic differentiation. Real-time polymerase chain reaction was performed to analyze the expression of osteoblast maker genes, and Western blot was used to verify the signaling pathway. Signaling pathway conformation, selective bone morphogenetic protein receptor inhibitor, and dorsomorphin homolog 1 were used as pretreatments before inducing osteogenic differentiation. We determined that MME (natural herb mixture extract) was a safe material and significantly increased osteoblast differentiation and that SMAD phosphorylation is a key signaling pathway that regulates osteogenic differentiation in hBMSCs. [ABSTRACT FROM AUTHOR]

Database security focuses on protecting most organization's virtual data storage unit and confidential information from malicious threats and external attacks. To keep out data secure, we need to use a role-based access control (RBAC) approach to accurately differentiate access permissions, but SQL queries written by an authorized user have very similar characteristics and are difficult to distinguish. In this paper, we propose a method of optimizing CNN-LSTM neural networks with particle swarm optimization (PSO) to classify the roles in RBAC system. Convolutional neural network (CNN) can extract parsed SQL queries into smaller details and features through an analysis mechanism. Long short-term memory (LSTM) is also suitable for modeling the temporal information of SQL queries to recognize the context of user authorities. PSO repeatedly searches and optimizes the complex hyperparameter space of the CNN-LSTM. Our PSO-based CNN-LSTM neural networks outperform other deep learning and machine learning models in the TPC-E benchmark SQL query statement. Finally, experiments and analysis show the usefulness of PSO and identify the important SQL query features that affect user role classification. [ABSTRACT FROM AUTHOR]

This study investigates the etiology and clinical features of delayed vitreous prolapse after cataract surgery and evaluates the long-term surgical and visual outcomes. Consecutive patients with vitreous prolapse into the anterior chamber occurring ≥ 3 months after cataract surgery at two hospitals between December 2006 and June 2020 were retrospectively reviewed. The primary outcome was associated ophthalmological events that triggered delayed vitreous prolapse. Secondary outcomes included long-term visual and subjective symptom changes after treatment. Among 20 eyes (20 patients), all had visual symptoms, the most common being blurry vision (12 patients; 60%). Five (25%) were detected after YAG laser capsulotomy, three (15%) had a history of intraocular lens(IOL) implantation in sulcus due to intraoperative posterior capsular tears, three (15%) had prolapsed vitreous alongside dislocated IOLs, and three (15%) were aphakic after previous cataract surgeries. After surgical treatment, the mean corrected distance visual acuity improved from 20/50 to 20/31(P = 0.02) and the mean preoperative intraocular pressure (IOP) that was 26.4 mmHg decreased to 15.6 mmHg, remaining stable until the last follow-up. All reported symptoms were relieved. YAG laser capsulotomy or a history of defective posterior capsule from iatrogenic causes may trigger delayed vitreous prolapse. The long-term outcomes were favorable, particularly after posterior vitrectomy, with improved IOP control and symptom resolution. [ABSTRACT FROM AUTHOR]

Matrix-assisted laser desorption ionization - mass spectrometry imaging of erlotinib reveals a limited tumor tissue distribution in a non-small-cell lung cancer mouse xenograft model GLO:F2H7/01jul21:ctm2481-fig-0002.jpg PHOTO (COLOR): 2 Erlotinib-resistant mouse xenograft model with H1299 cells and erlotinib distribution in tumor, liver, and kidney tissue. Although erlotinib still has a binding affinity to the target protein, EGFR, even in the H1299 tumor cells, the reduced distribution within in tumor tissues suggests a new mechanism of erlotinib resistance I in vivo i . H1299 tumor tissue, liver, and kidney were isolated from the xenograft mice previously treated with either vehicle ( I N i = 4) or erlotinib ( I N i = 5) (10 mg/kg) for analyzing erlotinib distribution. [Extracted from the article]

This study selects microalgae suitable for the decontamination of radioactive cobalt (Co-60) in radioactive solutions based on the decontamination efficiency of Co-60 and Cs-137 by various microalgae. The biosorption rates of Co-60 in the low-level contaminated water have been measured using three different types of microalgae Haematococcus sp., Vacuoliviride crystalliferum, and Chlorella vulgaris, which are known to uptake Cs-137 and Sr-90 effectively. In the comparative experiments, Haematococcus sp. showed the highest decontamination efficiency within 48 h, and it could be a suitable bio-adsorbent out of three types of microalgae for the removal of Co-60. Haematococcus sp. also removed 88.0% of Cs-137 from contaminated water for 48 h. Our findings indicated that the low-level radioactive solution was decontaminated to a very low-level state through the biosorption process of microalgae. [ABSTRACT FROM AUTHOR]

The rapid increase in human population and development in technology have sharply raised power consumption in today's world. Since electricity is consumed simultaneously as it is generated at the power plant, it is important to accurately predict the energy consumption in advance for stable power supply. In this paper, we propose a CNN-LSTM neural network that can extract spatial and temporal features to effectively predict the housing energy consumption. Experiments have shown that the CNN-LSTM neural network, which combines convolutional neural network (CNN) and long short-term memory (LSTM), can extract complex features of energy consumption. The CNN layer can extract the features between several variables affecting energy consumption, and the LSTM layer is appropriate for modeling temporal information of irregular trends in time series components. The proposed CNN-LSTM method achieves almost perfect prediction performance for electric energy consumption that was previously difficult to predict. Also, it records the smallest value of root mean square error compared to the conventional forecasting methods for the dataset on individual household power consumption. The empirical analysis of the variables confirms what affects to forecast the power consumption most. • We propose a novel deep learning model to stably predict electric energy consumption. • We analyze the model with the large data collected in an actual residential house. • We achieve the highest performance in high resolution compared with the previous works. • We explain the variables of appliances that influence the prediction performance. [ABSTRACT FROM AUTHOR]

Tetrahedral amorphous carbon (ta-C) film was prepared by the filtered vacuum arc process with Ar background gas. The residual compressive stress of the film decreased significantly as the Ar flow rate increased, whereas negligible change in the mechanical properties was observed. Structure analysis by Raman spectroscopy, near edge x-ray absorption fine structure, and electron spin resonance spectra revealed a close relationship between the residual compressive stress and the bond distortion that invokes paramagnetic defects or unpaired π electrons. These results demonstrate that the stress reduction can occur by relaxation of the distorted or twisted atomic bonds at the same fraction of sp3 hybridized bonds, which enhances the stability of the ta-C coating without deterioration in the advantageous properties. The effect of Ar background gas is discussed in terms of the increased ion population of low kinetic energy in the plasma beam. [ABSTRACT FROM AUTHOR]

Turbulence-chemistry interaction of inverse gaseous oxygen/hydrogen coaxial jet flames in a test model combustor at elevated and high pressures (up to 23.6 bar) has been studied experimentally. Since it is difficult to experimentally determine the Damkohler number (Da), an important parameter representing the turbulence-chemistry interaction, for turbulent nonpremixed flames, a new method to estimate Da using the flame visualization by OH planer laser induced fluorescence and OH∗ chemiluminescence is suggested. The proposed modified Da that is based on the flame base location where the maximum OH∗ intensity is observed and the mean OH layer thickness provides the limits for the occurrence of combustion instability leading to local flame extinction. Thus, it is found to be useful for representing the regimes that involve the local flame extinction, particularly when considering a wide range of pressure conditions where thermochemical and transport properties simultaneously vary and thus complicated phenomena are observed. The combustion instability is observed only for Da ≤ 0.4, and it is found that the OH layer thickness generally decreases, the disconnected OH reaction zone is reduced, the occurrence of the local flame extinction is suppressed and the maximum value of flame surface density is enhanced with increasing combustion pressure. Image 10370 • A database for modeling H 2 /O 2 bipropellant combustion at high pressure is provided. • A new method to estimate Damkohler number (Da) at various pressures is suggested. • Combustion stability of inverse H 2 /O 2 coaxial jet flames is represented using Da. • Occurrence of local flame extinction is suppressed at high pressure. • The maximum value of flame surface density is enhanced at high pressure. [ABSTRACT FROM AUTHOR]

Hybrid catalysts in a double-layered bed reactor were used to produce light C 2 –C 4 paraffin hydrocarbons. Combinations of Fischer–Tropsch (FT) and cracking catalysts in a double-layered bed reactor configuration were studied. SAPO-34 and Ni-based cracking catalysts (hybrid catalyst) were used to convert C 5+ into CH 4 and C 2 –C 4 paraffin hydrocarbons. Activity tests in the double-layered bed reactor at 10 bar and 300 °C and using a H 2 /CO feed gas ratio of 3.0 revealed that the hybrid catalyst showed lower C 5+ and higher CH 4 and C 2 –C 4 selectivities than the FT catalyst alone. The Ni-based catalyst enabled additional CO conversion and CO 2 methanation. Unlabelled Image • Fischer–Tropsch and cracking catalysts were combined in a double-layered bed reactor. • The hybrid catalyst in the double-layered bed reactor showed high light hydrocarbon selectivity. • SAPO-34 and Ni catalysts convert liquid and waxy hydrocarbons (C 5+) to CH 4 and C 2 –C 4. • The Ni catalyst enables additional CO conversion and CO 2 methanation. [ABSTRACT FROM AUTHOR]

Background: The aims of this study are to evaluate the usefulness of submucosal deformity pattern analysis with endoscopic ultrasonography (EUS) for predicting the depth of invasion in early gastric cancer (EGC) and the treatment results of endoscopic submucosal dissection (ESD).Methods: The endoscopic and EUS parameters of 345 patients with endoscopically suspected EGC who underwent endoscopic or surgical resection between July 2012 and May 2017 were retrospectively reviewed. All patients were classified into three categories as follows according to the morphologic type of submucosal deformity identified by EUS: (1) no submucosal deformity, (2) wedge-shaped deformity, and (3) arch-shaped deformity. The presence of an arch-shaped submucosal deformity on EUS and an active endoscopic ulcer or surrounding mucosal fold convergence/clubbing on conventional endoscopy were defined as suggestive of deep submucosal cancer invasion (SCI).Results: Upper location (p = 0.034) and the presence of an arch-shaped submucosal deformity on EUS (p < 0.001) were significant predictors of deep submucosal invasion, with the presence of an arch-shaped submucosal deformity showing the highest predictive value (odds ratio of 26.27). The overall diagnostic accuracy of EUS for predicting deep SCI was 83.5%, with a sensitivity of 84.0% and a specificity of 83.3%, which were significantly higher than those of conventional endoscopy. A larger lesion size and the presence of an arch-shaped submucosal deformity were significant factors associated with noncurative resection after ESD.Conclusions: Submucosal deformity pattern analysis with EUS can provide more accurate information than conventional endoscopy for predicting deep SCI. The presence of an arch-shaped submucosal deformity on EUS was an effective predictor of deep SCI and noncurative resection. [ABSTRACT FROM AUTHOR]

Graphical abstract Integrated process for the separation and recovery of Ag(I) from the nitrate solution used to leach the solar cell. Highlights • Ag(I) and Al(III) were separated from solar cell nitrate leachate with TOPO. • TOPO selectively extracted Ag(I) over Al(III) in 10 mol/m3 HNO 3 solution. • Selective stripping of Ag(I) was successful with 100 mol/m3 thiourea solution. • TOPO was regenerated by stripping of co-loaded Al(III) with 3000 mol/m3 HNO 3. Abstract For the recovery of Ag(I) from the leachate of silicon solar cells, a nitrate solution containing Ag(I) and Al(III) was subjected to solvent extraction with trioctylphosphine oxide (TOPO). TOPO selectively extracted Ag(I) over Al(III) at low nitric acid concentrations. Most of the Ag(I), along with small amount of Al(III), was extracted from the 10 mol/m3 nitric acid solution using 500 mol/m3 TOPO. HNO 3 stripped both Ag(I) and Al(III) from the metal-loaded TOPO, whereas thiourea could selectively strip Ag(I) from the loaded TOPO. Metal-loaded TOPO could be regenerated after stripping of Ag(I) with thiourea, followed by stripping of Al(III) with HNO 3. A process flow sheet for Ag(I) recovery from the nitrate leachate of silicon solar cells was proposed. [ABSTRACT FROM AUTHOR]

Background: Tranexamic acid (TXA) has been demonstrated to minimize blood loss after total hip arthroplasty. There are three main routes: intravenous (IV), intra-articular (topical), and combined (IV and topical) but little consensus support which is most effective and safe. We performed network meta-analysis.to assess the comparative efficacy and safety of three different administration routes of TXA. Methods: Twenty-five randomized controlled trials (RCT) were evaluated. Interventions were classified as: combined, IV multiple, IV single, topical and placebo. The primary outcome was effectiveness (transfusion rate, total blood loss, and total drain out). The secondary outcome was safety, based on the incidence of deep venous thrombosis (DVT) and pulmonary embolism (PE). Results: A total of 2227 patients were included in the 5 categories: 564 IV single, 319 IV multiple, 398 topical, 120 combined, and 826 placebo. A network meta-analysis identified the most effective interventions in terms of reducing the need for transfusion as follows: combined = 98.2%, IV single = 54.0%, IV multiple = 78.6%, topical = 66.1%, placebo = 0.0%. Compared with placebo, the IV single, IV multiple, topical, and combined interventions showed no difference in the rate of occurrence of DVT and PE. Conclusions: A network meta-analysis indicated that combined administration of TXA (IV and topical) was effective in reducing the transfusion rate after hip arthroplasty compared with IV or topical alone. As no high-risk patients were evaluated in the RCTs, it is not known whether the combined method is safer for patients susceptible to DVT or PE. [ABSTRACT FROM AUTHOR]

Web traffic refers to the amount of data that is sent and received by people visiting online websites. Web traffic anomalies represent abnormal changes in time series traffic, and it is important to perform detection quickly and accurately for the efficient operation of complex computer networks systems. In this paper, we propose a C-LSTM neural network for effectively modeling the spatial and temporal information contained in traffic data, which is a one-dimensional time series signal. We also provide a method for automatically extracting robust features of spatial-temporal information from raw data. Experiments demonstrate that our C-LSTM method can extract more complex features by combining a convolutional neural network (CNN), long short-term memory (LSTM), and deep neural network (DNN). The CNN layer is used to reduce the frequency variation in spatial information; the LSTM layer is suitable for modeling time information; and the DNN layer is used to map data into a more separable space. Our C-LSTM method also achieves nearly perfect anomaly detection performance for web traffic data, even for very similar signals that were previously considered to be very difficult to classify. Finally, the C-LSTM method outperforms other state-of-the-art machine learning techniques on Yahoo's well-known Webscope S5 dataset, achieving an overall accuracy of 98.6% and recall of 89.7% on the test dataset. [ABSTRACT FROM AUTHOR]

To effectively design hydrogen (H 2 )/oxygen (O 2 ) liquid rocket engines through understanding the combustion characteristics of H 2 /O 2 bipropellants, fundamental studies for the bipropellants in different phases are needed. This study is focused on the combustion characteristics of inverse gaseous O 2 /H 2 coaxial jet flames in a single-element model combustor as a preliminary step for succeeding studies of injection at different phases in the combustor, visualizing flame structure by direct imaging, OH ∗ chemiluminescence and OH planar laser-induced fluorescence. With increasing Reynolds number (Re), the frequency of occurrence of the local flame extinction increases and the length of the disconnected OH reaction zone is extended. The OH layer thickness increases downstream, while it is almost constant where the local flame extinction occurs and decreases with increasing Re due to the enhanced strain and scalar-dissipation rates. The excessive flame wrinkledness increases the local flame strain rate and results in the local flame extinction, exhibiting the tendency of increasing and then decreasing flame surface density with increasing Re. The probability density function of OH intensity quantifies the fluctuation intensity of OH radicals and the possibility of the local flame extinction. A useful database is provided for modeling the combustion of H 2 /O 2 bipropellants under different phases. [ABSTRACT FROM AUTHOR]

Abstract: 4D printing is an extension to 3D printing whereby a printed shape programmatically undergoes shape transformation through external stimulations. There is an increasing interest in this field because of its potential applications. However, many demonstrated shape transformations work on simple and limited geometrical shapes. In this work, the formation of a cylinder from a printed flat dual‐layer beam when exposed to ethanol is demonstrated. The newly formed cylinder retains its shape even when the ethanol is removed through the use of a locking mechanism. The proposed method can be used for building medical stents or various sensors and actuators that require cylindrical shapes. [ABSTRACT FROM AUTHOR]

The sources of different pollutants contributing to ambient fine particles (PM 2.5 ) on Daebu Island, Korea, were estimated. Twenty four hour integrated filter samples were collected from May 21–November 1, 2016, and analyzed for organic carbon, elemental carbon, ions, and trace elements. Positive matrix factorization was conducted on the PM 2.5 chemical speciation data from the samples to define the pathways and sources of PM 2.5 at the sampling site. A total of 80 samples and 24 chemical species were used to run the model and a total of nine sources were identified: secondary sulfate (29.0%), mobile (22.0%), secondary nitrate (13.2%), oil combustion (10.1%), coal combustion (9.4%), aged sea salt (7.9%), soil (5.6%), non-ferrous smelting (1.7%), and industrial activity (1.1%). Conditional probability and potential source contribution functions were then used to determine whether these sources were local or came from pollutants transported over long-range distances. The anthropogenic sources came from local emissions and originated from both industrialized and metropolitan areas, whereas the secondary inorganic aerosols were strongly influenced by the long-range transport of air pollutants from Shandong and Jiangsu provinces in China. [ABSTRACT FROM AUTHOR]

In this study, the waste heat recovery performance of a hexagonal thermoelectric generator (TEG) was investigated experimentally. Based on the system configuration and dimensions, a total of 18 thermoelectric modules (TEMs) were used for thermal energy harvesting. The internal finned structures of the hexagonal TEG were placed on the inner surface of the exhaust gas channel, in consideration of the thermal resistance and friction factor, in order to augment the heat transfer from the exhaust gas to the thermoelectric modules (TEMs), under various operating conditions. The surface of the TEMs was positioned on the hexagonal-shaped exhaust gas channel surface, whereas the other surface of the TEMs was maintained cool by a set of coolers through which the engine coolant flowed. The coolant line was modified in order to induce a total coolant flow of 10 LPM at 353 K from a coolant controller to the hexagonal TEG. In this study, the assembled hexagonal TEG was installed in the middle of the exhaust gas pipe of the internal combustion engine manufactured for hybrid electric vehicles, and was used as the heat source. The waste heat recovery performance of the hexagonal TEG was evaluated by considering eight engine-operating conditions under which the automotive vehicles were most frequently driven. The output power of the hexagonal TEG tended to increase with the increase in engine speed and load, and ranged between 21.2 and 98.8 W, which corresponded to a conversion efficiency of ∼1.3–2.6%. An acceptable maximum pressure drop across the hexagonal TEG of ∼2.1 kPa was observed for the maximum exhaust gas flow rate condition. [ABSTRACT FROM AUTHOR]

The objective of the present study is to assess the potential of energy recovery from the exhaust gas of a passenger car engine under various driving drive cycles using a thermoelectric generator (TEG). This study investigates energy recovery using a steady-state engine experiment and a one-dimensional (1-D) transient cycle simulation. A1-D TEG system simulation model was developed for a TEG system consisting of 40 TEG modules. This simulation model was then validated based on steady-state experimental results. The comparison showed good agreement between the model and experimental results. Under medium engine load conditions, the discrepancy between the two results was 3%. Then, the validated TEG model was employed for drive cycle simulations to estimate the performance of the TEG system under the various driving conditions. Four regulatory test drive cycles were used in the simulations, namely, Federal test protocol 75, the Highway Fuel Economy test, the common Artemis Drive Cycle for rural roads, and the Worldwide Harmonized Light Vehicles test cycle. The simulation results showed that the TEG system contributed to power increases ranging from 1.54 to 1.68%, depending on the drive cycles. [ABSTRACT FROM AUTHOR]

Studies examining the association between alcohol intake and the risk of osteonecrosis of the femoral head (ONFH) have inconsistent results. The purpose of this study was to examine and summarize the evidence regarding the association between alcohol intake and ONFH based on results from case-control studies. This analysis included five case-control studies reporting data from 1251 individuals. Alcohol intake habits (never, former, or current), average drinking consumption (g/week), and cumulative drinking consumption (drink-years) were extracted. The risk of ONFH was evaluated, and a two-stage dose-response meta-analysis was performed using restricted cubic splines with four knots at fixed percentiles of 5, 35, 65, and 95% of the distribution. Former alcohol intake increased the risk of ONFH with a marginal significance (odds ratio [OR], 2.62; p = 0.055). Current alcohol intake was associated with an increased risk of ONFH (OR, 3.63; p < 0.001 in occasional drinkers, OR, 5.90; p < 0.001 in daily drinkers). The dose-response meta-analysis revealed that the risk of ONFH increased by 35.3% for every 100 g/week (95% confidence interval [CI], 1.24-1.47; p < 0.001) and by 44.1% for every 500 g drink-years (95% CI, 1.295-1.601; p < 0.001). Current intake and the dose of alcohol were positively associated with an increased risk of ONFH in a non-linear pattern. [ABSTRACT FROM AUTHOR]

A protocol for quantitative image analysis of wound generation is important to better understand the integrative process of wound healing and the closure mechanism. Here, we present a method for quantitative analysis of microscopic images of circular wound sites generated by vertically stamped scratches. To demonstrate proof-of-concept validation, we used two types of mechanical stamping tools, a mechanical pencil lead (type 1; brittle) and polydimethylsiloxane (PDMS) pillars (type 2; ductile), to create circular wound sites. We also present a method for analysis of microscopic images of the generated wound sites by suggesting new parameters, such as controlled area transfer ratio, modified shape factor, and roundness index, specifically to investigate the shape and size of wounds via house-coded image processing. We believe that this approach can be potentially useful by providing a better way of studying vertical wound generation for future skin wound generation and care applications compared with its counterpart, conventional horizontal wound generation. [ABSTRACT FROM AUTHOR]

In order to understand the combustion stability of a methane (CH 4 )/oxygen (O 2 ) bipropellant as a next-generation rocket liquid propellant, the combustion stability limits and morphology of gaseous CH 4 /O 2 (GCH 4 /GO 2 ) coaxial jet flames, among various phases, in a single-element combustor are experimentally studied compared with the gaseous hydrogen/O 2 (GH 2 /GO 2 ) coaxial jet flames. Only the stably attached flame and blowoff regimes are observed for both the GCH 4 /GO 2 and GH 2 /GO 2 flames, showing the flame thickness smaller than the injector lip thickness. Although the combustion stability limits of the GCH 4 /GO 2 flames are narrower than the GH 2 /GO 2 flames, practical use of CH 4 in rocket engine applications seems to be acceptable since the fuel-rich CH 4 /O 2 flames show very stabilized and intensified burning. For the GCH 4 /GO 2 flames, the outer flame generated by the recirculating O 2 is relatively weak and OH ∗ is distributed up to the downstream. With increasing O 2 injection velocity the length of the GCH 4 /GO 2 flames and the location at the maximum OH ∗ intensity increase even under turbulent combustion condition, due to the saturated enhancement of CH 4 -O 2 diffusivity and the strong burning of pure O 2 near the injector lip. The present results provide a useful database to model combustion of CH 4 /O 2 bipropellants under various phases. [ABSTRACT FROM AUTHOR]

This paper proposes the concept of a direct contact thermoelectric generator (DCTEG) to enhance the practicality and widen the application areas of thermoelectric generators (TEGs). In the DCTEG, one thermoelectric module (TEM) surface is directly exposed to a heat source, and the other surface is in direct contact with a coolant flow. The current direct-contact configuration is beneficial for system fabrication, maintenance, long-term reliability, and maximizing energy usage in cooperation with other energy systems because of its simple configuration and lack of interfaces between the TEMs and heat sources. In order to validate the proposed concept experimentally, a DCTEG was constructed by fabricating customized TEMs and exhaust gas and coolant channels with openings to mount the TEMs. A diesel engine served as a heat source by providing hot exhaust gas into the DCTEG, while the coolant (water–ethylene glycol mixture) was pumped into the coolant channels to remove heat. Based on the experimental results obtained under various engine operating conditions, the power generation of the DCTEG was characterized in the form of current–voltage and power–voltage curves. The maximum output power of 43 W and conversion efficiency of 2.0% were obtained under the highest engine load and rotation speed conditions. A series of numerical simulations was carried out to investigate the effect of the system configuration on the DCTEG power generation performance with the clearance between the TEM surfaces and exhaust gas/coolant channel surfaces as a key parameter. Based on the validated numerical results and single-module-based experimental results, a 132% increase in power output and 23% decrease in pressure drop are predicted for a configuration with TEMs flush-mounted to the exhaust gas and coolant channels compared to the original DCTEG configuration used in the experiment. The overall experimental and numerical results support the feasibility of the DCTEG concept and its potential for increasing the applicability of TEGs in various engineering fields. [ABSTRACT FROM AUTHOR]

An experimental study was undertaken to investigate the effect of the electrical array configuration of thermoelectric modules (TEMs) on thermoelectric power generation. A thermoelectric generator (TEG) was constructed with customized TEMs. Prior to the system-wise power generation experiment, the electrical characteristics of each TEM (a total of ten TEMs) were measured. The sum power output of each TEM was 34.2 W, which was set as a reference power output for different system-wise array configuration methods To examine the effect of the array configuration, eight different TEM array configurations were formed using series, parallel, and combination connections to provide different power sources for different applications. The experimental results showed that the system-wise power output of the different array configurations varied up to 59% compared to the reference power. Moreover, a 1.4–36.4% difference in power output was evident compared to the individual array configuration on account of the different ways in which the TEMs were electrically connected. The number of junctions in the circuitry and the unbalanced number of modules in the array configuration were chosen as the possible parameters that mostly affected the power output in various electrical circuitries for a constant temperature difference across the TEM sides. Consequently, the power output of the TEG decreased with the increasing number of circuitry junctions in the TEG. The array configuration with less than two junctions in its circuitry showed a power generation up to 94%, whereas the array configuration with six junctions generated only up to 62.5% compared to the reference power output. Similarly, the power output of the TEG decreased with the increasing unbalanced number of modules in the circuitry. The power generation of TEG array configurations with a balanced number of modules in the array was up to 95.4%, whereas that with four unbalanced number of modules in the array only generated 58.9% compared to the reference power output. Therefore, the array configuration with a minimized number of junctions and balanced number of modules is recommended for maximizing the TEG power output. [ABSTRACT FROM AUTHOR]

This study was devoted to investigating the energy utilization of a thermoelectric generator (TEG). Key factors governing the power generation characteristics of the TEG—the power output, system resistance, and conversion efficiency—are systematically analyzed under various engine operating conditions. The effects of heat rejection conditions on the energy utilization by the TEG are also examined. Experimental results show that a slight coolant temperature reduction of 10 K increases the TEG power output by up to 33.7%, increasing the short-circuit current. The coolant temperature reduction also causes more than 34.8% improvement in the conversion efficiency. Contour maps for the power output and conversion efficiency are proposed as functions of the engine load and speed. A maximum power output and conversion efficiency obtained are ∼125.7 W and ∼3.0%, respectively. In contrast to the coolant temperature effect, a change in the coolant flow rate has a relatively insignificant effect on energy utilization: the power output variation is only 6.8%–8.5%. The TEG design effectiveness is evaluated by analyzing the flow of exhaust gas energy. The analysis shows that a relatively large portion of exhaust gas energy (37.4%–47.1%) is lost to the environment instead of being used for power generation by the TEG. [ABSTRACT FROM AUTHOR]

In this study, waste heat recovery performance of a direct contact thermoelectric generator (DCTEG) is experimentally investigated on a diesel engine. In order to conduct an insightful analysis of the DCTEG characteristics, three experimental parameters—engine load, rotation speed, and coolant temperature—are chosen to vary over ranges during the experiments. Experimental results show that higher temperature differences across thermoelectric modules (TEM), larger engine loads, and rotation speeds lead to an improved energy conversion efficiency of the DCTEG, which lies in the range of approximately 1.0–2.0%, while the output power ranges approximately 12–45 W. The increase in the conversion efficiency for an increased engine load becomes more noticeable with a higher engine rotation speed. A 10 K decrease in the coolant temperature yields an approximately 0.25% increase in the conversion efficiency for the engine operating conditions tested. In addition, 3D numerical simulations were conducted to investigate the heat transfer and pressure characteristics of the DCTEG. Numerically obtained exhaust gas temperatures exiting the DCTEG were in good agreement with experimental results. It is also revealed that incorporation of the temperature fields from the numerical simulation and an empirical correlation for a temperature-power relationship provides a good predictor for output power from the DCTEG, especially at low engine load conditions, which deviates from experimental results as the engine load increases. Heat recovery efficiency of the DCTEG is found to be in the range of approximately 5.7–11.1%, which is yielded by comparing the heat transfer rate from the exhaust gas to a surface of the TEMs to the total exhaust gas energy entering the DCTEG. Numerical results also show that most exhaust gas thermal energy extracted by the DCTEG is used for thermoelectric energy conversion, and only approximately 1/5 of the energy is wasted to the environment regardless of engine load conditions. Owing to a simple internal geometry without any extended surfaces, the DCTEG features a low exhaust gas pressure drop of smaller than 700 Pa even for the maximum exhaust gas flow rate of approximately 322 kg/h. [ABSTRACT FROM AUTHOR]

A novel configuration of a heat-recirculating combustor with multiple injectors for 10–30 W power-generating thermophotovoltaic (TPV) systems is suggested. For the combustor as a heat source the combustion stability limits of premixed butane-air flames, the temperature distribution on the outer wall surface and the spectral emissive power density onto photovoltaic cells are measured to evaluate the combustion and radiation performance. Results show that the combustor can sustain stable burning and effective and uniform heat transfer for a wide operating range, due to the heat-recirculation using a cylindrical emitter with a quartz shield and a recuperator. Two distinct combustion stability limits, i.e., flashback and blowout limits, are observed, and a somewhat extended stable-burning regime is found for the combustor with a finned recuperator and closer injectors. The recuperator and injector geometry also affects the temperature distribution on the emitter wall surface. A silicon carbide (SiC) emitter shows higher spectral emissive power density than the stainless steel emitter, due to higher surface temperature and emissivity, and the emissive power density is further enhanced by applying the photonic crystal structure on the SiC emitter surface, due to the optical resonance effects. Thus, the present combustor configuration can be used in practical TPV power systems. [ABSTRACT FROM AUTHOR]

Background: Hip fracture is a common health problem in the elderly that is associated with increased mortality. Acute kidney injury (AKI) is a frequent complication in elderly patients undergoing surgery and is associated with the clinical outcome. We evaluated the incidence and risk factors of AKI in elderly patients undergoing hip fracture surgery and the impact of AKI on short- and long-term clinical outcomes. Methods: We performed a retrospective cohort study of 450 elderly patients who underwent hip fracture surgery between January 2010 and December 2012. We defined AKI according to the Acute Kidney Injury Network (AKIN) criteria and investigated the effect of AKI on the duration of hospital stay and in-hospital and long-term mortality. Results: Of the 450 patients, 95 (21.1%) developed AKI during hospitalization and 178 (39.6%) died, with a mean follow-up of 3.6 ± 1.0 years. The baseline serum creatinine level, use of angiotensin-converting enzyme inhibitors or angiotensin-II receptor antagonists, red blood cell transfusion volume, and history of coronary artery disease were independent risk factors for AKI. Patients with AKI during hospitalization had significantly longer hospital stays and higher in-hospital and long-term mortality than those without AKI. Multivariate analysis revealed that age, history of coronary artery disease, serum albumin level, and AKI were independent predictors of long-term mortality. Conclusions: AKI is a frequent complication in elderly patients undergoing hip fracture surgery and is independently associated with increased in-hospital and long-term mortality. [ABSTRACT FROM AUTHOR]

This study investigated factors influencing the demotivation and remotivation of Korean high school EFL students. Sixty-four grade 11 students were asked to draw a graph mapping their changes in English learning motivation from kindergarten to high school. From these, the data of 15 students who showed a decline in motivation and 13 students who showed a decline followed by an increase in motivation were chosen for further participation. These participants were asked to state the reasons for their motivational changes in response to an open-ended questionnaire, after which follow-up interviews were conducted. The results revealed that the majority of the participants became most demotivated in junior high school, mainly due to external factors, such as ineffective teaching methods, learning difficulty, and social pressure. However, 13 learners also experienced noticeable remotivation due to both external and internal factors. Major external remotivation factors included changes in study methods and inspiration from classmates, whereas the main internal factors were increased awareness of the necessity of English for the future, experiences of success, and interest in English culture. Based on these findings, pedagogical implications are provided. [ABSTRACT FROM AUTHOR]

Fundamental combustion properties of gaseous methane (CH 4 )/oxygen (O 2 ) coaxial jet flames in a single-element combustor are experimentally evaluated as a preliminary step for subsequent studies of injection at very low temperature or using liquid O 2 for CH 4 /O 2 bipropellants, recently appearing to be the oncoming liquid bipropellant. A combustion chamber with quartz windows, a single shear coaxial injector and an exhaust nozzle on the downstream of the chamber is considered for the present study. Focusing on the measurements of the ignition and combustion stability limits of the coaxial jet flames in the chamber, flame visualization is also conducted by OH ∗ chemiluminescence, schlieren imaging and direct imaging. Results show the ignition limits restricted than the combustion stability limits. Flame behaviors are largely classified into two, the stably attached flame and the oscillating, liftoff (near-blowout) flame. Due to cooling effects on the wall of the chamber, stably liftoff flame is not observed. The stability of the flame is greatest at fuel-rich condition (based on the injected amounts of CH 4 and O 2 ). From the flame visualization flame thickness is found to be smaller than the injector lip thickness and insensitive to injection conditions. The laminar-flow behavior near the injector exit due to the strong burning of pure O 2 is observed even for high Reynolds numbers ( Re ). The flame visualization also exhibits the recirculating O 2 that enhances burning in the combustor through the reaction with the outer fuel jet. The results of ignition limits, combustion stability limits and flame visualization can be used as a database for researches of modeling the gaseous CH 4 /O 2 jet flames in the combustion chamber. [ABSTRACT FROM AUTHOR]

The combustion and emission characteristics of a stratified lean-burn liquefied petroleum gas (LPG) direct-injection engine are investigated at five representative engine operating points, where passenger vehicles are most frequently operated. A redesigned engine head that makes room for an injection and ignition assembly, comprised of a center-mounted fuel injector and a spark plug positioned in the vicinity of the fuel injector, made the spray-guided LPG lean-burn possible. The experimental results show that the stratified LPG lean-burning achieves a 10.2–27.5% improvement in the brake specific fuel consumption (BSFC), while reducing NO x emissions by 72.0–83.4% compared to that obtained through homogeneous stoichiometric combustion. Decreased pumping loss and enhanced combustion speed led by the adoption of the stratified lean combustion strategy play a key role in improving the combustion performance. A cooled exhaust gas recirculation (EGR) system was also introduced for further reduction of NO x emissions for low engine load conditions It was determined that the most adequate EGR rate of 15% magnifies the benefits of the NO x reduction in the stratified lean-burning, providing additional reductions of 34.4–46.5%. The application of cooled EGR, however, led to slight fuel economy penalties yielding a 1.6–2.5% increase in the BSFC. [ABSTRACT FROM AUTHOR]

5-Lipoxygenase (5-LOX) is an enzyme that converts arachidonic acid from the cell membrane into leukotriene, a signal lipid mediator. 5-LOX deficiency markedly attenuates the formation of aneurysms in knockout mice. In addition, Zileuton, a clinical drug targeting 5-LOX, is used for treatment of asthma. However, it is unclear whether 5-LOX inhibition results in anti-angiogenic effects for applications in cancer therapy. To explore the roles of 5-LOX in angiogenesis and its potential as a therapeutic target in cancer, the effects of a newly synthesized 5-LOX inhibitor, F3 , on in vitro and in vivo angiogenesis were investigated. The results showed that 5-LOX inhibition by F3 suppressed in vitro vascular endothelial growth factor (VEGF)-induced tube formation and chemo-invasion of endothelial cells (ECs). 5-LOX inhibition also decreased VEGF-induced extracellular signal-regulated kinase (ERK) phosphorylation in ECs. Notably, 5-LOX knockdown phenocopied the anti-angiogenic activity of the 5-LOX inhibitor F3 in a concentration-dependent manner. F3 did not affect the activities of VEGF receptor 2 or AKT. In vivo , the compound significantly inhibited the formation of the chorioallantoic membrane at nontoxic doses. These results demonstrated that 5-LOX played an important role in angiogenesis and that its inhibitor F3 could be a new anti-angiogenic agent targeting VEGF signaling. [ABSTRACT FROM AUTHOR]

The waste heat recovery performance of a thermoelectric generator (TEG) was experimentally investigated. Forty customized thermoelectric modules (TEMs) were installed on the upper and lower sides of a rectangular exhaust gas channel in a 4 × 5 arrangement. Water at an ambient temperature of ∼293 K was supplied from a cooling tower and was used to create a temperature difference across each TEM. The water flow rate was fixed at 8 SLPM. A turbocharged six-cylinder diesel engine was used as the heat source; the engine was operated under various conditions. Three engine rotation speeds—1000, 1500, and 2000 rpm—were employed to determine the effect of the exhaust gas flow rate on the TEG power output. The temperature of the exhaust gas was varied by changing the engine load, i.e., the brake mean effective pressure (BMEP), at an interval of 0.2 MPa. From the experimental results, a contour map showing the power output of the TEG as a function of the engine load and speed was obtained. From the contour map, we observed that the power output of the TEG increases with the engine load or speed. The maximum power output was ∼119 W at 2000 rpm with a BMEP of 0.6 MPa; the maximum energy conversion efficiency was ∼2.8%. The pressure drop across the TEG was experimentally found to be 0.45–1.46 kPa under all engine operation conditions. [ABSTRACT FROM AUTHOR]

Thermoelectric modules (TEMs) are fabricated for a low-temperature waste heat recovery application. Each module has a surface area of 44 × 44 mm and a thickness of 3.6 mm, including a 1-mm-thick ceramic substrate on each side. Prior to fabrication of the system, a series of numerical simulations are conducted to optimize the design of the internal finned structures of a thermoelectric generator. To reduce the difficulty of designing the numerical models, a thermal resistance model is employed to determine the thermal conductivity of the TEM. The optimal number and thickness of the fin structures are determined with respect to the maximum allowable module temperature and the pressure drop characteristics. The accuracy of the numerical model is validated using an existing friction factor correlation and experimental results. The numerical results show that having six 2-mm-thick plate fins on the hot surface of each TEM would provide the most effective temperature fields for TE power generation while keeping the surface temperature of the TEM from exceeding the allowable maximum of ∼473 K. The pressure drop across the fins is found to increase with increasing number and thickness of fins. However, the module-level pressure drop is in the range of several pascals, which has a negligible effect on the combustion characteristics of the engine. A thermal resistance equation is proposed to predict the heat transfer characteristics of plate fins employed for thermoelectric generators for heat absorption. [ABSTRACT FROM AUTHOR]