Compositions of Gamma and Gamma Prime Phases in an As-Cast Nickel-Based Single Crystal Superalloy Turbine Blade

The core and the interdendritic regions of an as-cast nickel based single crystal turbine blade were observed by electron microscopy to understand the microstructural development during an investment casting process. The dendrite core region shows an irregular morphology of gamma prime in gamma due to a relatively short casting time, which prevented the development of gamma prime expected in a solution heat-treated microstructure. By comparison, the interdendritic region comprises three different regions composed of: several elongated gamma prime particles, relatively tiny and irregular gamma prime, and gamma prime with relatively regular morphology. The chemical analysis of these phases showed that, regardless of the analysis point in the core or the interdendritic region, almost the same compositions were acquired in the regular type of gamma and gamma prime phases. This result suggests that if the gamma prime forms in the gamma matrix, the composition of gamma prime is almost uniform regardless of the region and prevailing general chemical composition. In contrast, the composition of the elongated gamma prime in the interdendritic region was slightly different depending on the analysis point even within the same elongated particle

Establishment and Characterization of an In Vitro Model for Cholesteatoma

ObjectivesExperimental models are of importance to study the pathogenesis of middle ear cholesteatoma, however, they were not established until now. We aimed to develop in vitro model of middle ear cholesteatoma using primary keratinocytes and fibroblasts isolated from cholesteatoma tissue. HaCaT cell line was used as a "skin equivalent" and to compare the grade of homogeneity between cholesteatoma keratinocytes and HaCaT cells.MethodsPrimary keratinocytes were isolated from cholesteatoma tissue, co-cultured with preliminary prepared feeder layer from cholesteatoma fibroblasts and subsequently air-exposed. The protein profile of cholesteatoma keratinocytes and HaCaT cells was evaluated by means of immunoblot using monoclonal antibody against cytokeratin (CK) 13 and 16. Tissue localization of CK 13 and 16 was accomplished with immunohistochemistry.ResultsDifferent protein profile and stronger expression of CK 13 and 16 were demonstrated in cholesteatoma keratinocytes in comparison with HaCaT cells. Bigger stratification was observed in the 3D-in vitro systems when both cholesteatoma keratinocytes and HaCaT cells were respectively co-cultured with fibroblasts in comparison with the corresponding control groups without fibroblasts.Conclusion3D-model demonstrates the significance of intercellular interaction between components of cholesteatoma tissue

Congenital Stapes Anomalies with Normal Eardrum

ObjectivesA non-progressive and conductive hearing loss with normal eardrum, but no history of trauma and infection, is highly suggestive of a congenital ossicular malformation. Among ossicular anomalies, stapes anomaly is the most common. The purpose of this study is to describe patterns of stapes anomaly and to analyze its surgical outcome with special reference to its patterns.MethodsWe conducted a retrospective case review. The subjects comprised 66 patients (76 ears) who were decisively confirmed by the exploratory tympanotomy as congenital stapes anomalies without any anomalies of the tympanic membrane and external auditory canal. The preoperative and postoperative audiological findings, temporal bone computed tomography scan, and operative findings were analyzed.ResultsThere were 16 anomalous patterns of stapes among which footplate fixation was the most common anomaly. These 16 patterns were classified into 4 types according to the status of stapes footplate. Successful hearing gain was achieved in 51 out of 76 ears (67.1%) after surgical treatment.ConclusionFootplate fixation was usually bilateral, whereas stapes anomalies associated with other ossicular anomaly were usually unilateral. The success of the surgical treatment of stapes anomaly might depend on its developmental status of the footplate. Stapes anomalies were detected without any fixed patterns, therefore, it is quite possible to detect a large variety of patterns in future

Management for the Children with Otitis Media with Effusion in the Tertiary Hospital

ObjectivesRecently, new evidence-based recommendations have been introduced for diagnosing and managing otitis media with effusion (OME) in children. However, there are some difficulties to follow the general guidelines in the tertiary hospitals. The purpose is to evaluate the efficiency of antibiotics or antihistamines for treatment of children with OME in the tertiary hospital with a randomized prospective clinical study.MethodsEighty-four children with OME who had been diagnosed in the tertiary hospital were randomized to receive 5 different medications for 2 weeks. We prescribed antibiotics (amoxicillin-clavulanate syrup) in Group I (n=16), antibiotics/steroids (prednisolone) in Group II (n=18), antibiotics/antihistamines (ebastine) in Group III (n=15), antibiotics/steroids/antihistamines in Group IV (n=17), and mucolytics (ivy leaf extract) in Group V (n=17) for control. We followed-up children every 2 weeks and evaluated the state of OME at 3 months.ResultsThirty six (42.9%) of 84 children were resolved within average 6.9 weeks after the treatments. Thirty-six (42.9%) were treated with ventilation tube insertion and 12 patients (14.3%) were observed. There was no difference in the resolution rates of OME among the five different protocols (P>0.05). There was no difference in the resolution rates among groups who used steroids, antihistamines, steroids and antihistamines, or other medications to manage 42 children with allergies (P>0.05).ConclusionIn the tertiary hospital, the cure rate of children with OME was not as high as well-known, and antibiotics or anti-allergic medications were not more effective than control. We may, therefore, need any other guidelines which are different from the previous evidence-based recommendations, including early operation in the tertiary hospitals

A Dynamic Plane Prediction Method Using the Extended Frame in Smart Dust IoT Environments

Internet of Things (IoT) technologies are undeniably already all around us, as we stand at the cusp of the next generation of IoT technologies. Indeed, the next-generation of IoT technologies are evolving before IoT technologies have been fully adopted, and smart dust IoT technology is one such example. The concept of smart dust IoT technology, which features very small devices with low computing power, is a revolutionary and innovative concept that enables many things that were previously unimaginable, but at the same time creates unresolved problems. One of the biggest problems is the bottlenecks in data transmission that can be caused by this large number of devices. The bottleneck problem was solved with the Dual Plane Development Kit (DPDK) architecture. However, the DPDK solution created an unexpected new problem, which is called the mixed packet problem. The mixed packet problem, which occurs when a large number of data packets and control packets mix and change at a rapid rate, can slow a system significantly. In this paper, we propose a dynamic partitioning algorithm that solves the mixed packet problem by physically separating the planes and using a learning algorithm to determine the ratio of separated planes. In addition, we propose a training data model eXtended Permuted Frame (XPF) that innovatively increases the number of training data to reflect the packet characteristics of the system. By solving the mixed packet problem in this way, it was found that the proposed dynamic partitioning algorithm performed about 72% better than the general DPDK environment, and 88% closer to the ideal environment

An IoT System for Remote Monitoring of Patients at Home

Application areas that utilize the concept of IoT can be broadened to healthcare or remote monitoring areas. In this paper, a remote monitoring system for patients at home in IoT environments is proposed, constructed, and evaluated through several experiments. To make it operable in IoT environments, a protocol conversion scheme between ISO/IEEE 11073 protocol and oneM2M protocol, and a Multiclass Q-learning scheduling algorithm based on the urgency of biomedical data delivery to medical staff are proposed. In addition, for the sake of patients’ privacy, two security schemes are proposed—the separate storage scheme of data in parts and the Buddy-ACK authorization scheme. The experiment on the constructed system showed that the system worked well and the Multiclass Q-learning scheduling algorithm performs better than the Multiclass Based Dynamic Priority scheduling algorithm. We also found that the throughputs of the Multiclass Q-learning scheduling algorithm increase almost linearly as the measurement time increases, whereas the throughputs of the Multiclass Based Dynamic Priority algorithm increase with decreases in the increasing ratio

General View of Rhenium-Rich Particles along Defect Grain Boundaries Formed in Nickel-Based Single-Crystal Superalloy Turbine Blades: Formation, Dissolution and Comparison with Other Phases

Nickel-based single-crystal superalloy turbine blades have been widely used in engines of aircrafts or power plants, but some defect grains are often found on the surface of the blade after full heat treatment or even after casting. Rhenium-rich particles, as well as an intermediate layer, were almost always detected along any defect grain boundary region, if it existed, from a low-angle grain boundary to a high-angle boundary. The particles were also found on the top surface of the base material. The composition and morphology of the particles were different from the most common topologically close packed phases or a fine particle with similar morphology detected at the boundary region between a recrystallized grain and a matrix grain. An additional heat treatment could completely dissolve the fine particles. Furthermore, any rhenium-rich particles were not re-formed after achieving uniform distribution of the alloying elements

A Two-Class Data Transmission Method Using a Lightweight Blockchain Structure for Secure Smart Dust IoT Environments

In smart dust IoT environments, a large number of devices with low computing power/resources are deployed to collect surrounding information. There are many issues to consider for an efficient and secure smart dust IoT environment. Sometimes the urgent sensed data needs to be transmitted immediately. In addition, there are potential problems related to security issues since the smart dust IoT systems may be deployed in hard-to-access areas. In this paper, we propose an effective transmission method for two-class sensed data for secure smart IoT systems. We divide the sensed data into two classes which consist of the urgent sensed data class (requiring urgent data transmission) and the normal sensed data class (with a slight transmission delay due to yielding to the urgent data transmission). In addition, for security reasons, the proposed transmission method uses two kinds of blockchains with the following two ledgers: (1) the urgent sensed data ledger, which is a ledger of data that needs urgent transmission; and (2) the normal sensed data ledger, which is a ledger of data that allows some delay. To be specific, the lightweight blockchain based on our earlier work is used for the normal sensed data transmission, whereas the modified conventional blockchain is used for the normal sensed data transmission. The experiments show that the performance of the proposed transmission method is better than the conventional transmission method in almost all sections. There is a 53% performance increase on average with regard to the transmission time. When the ratio of urgent sensed data is 0% (i.e., no urgent sensed data at all), the proposed transmission method is greater improved by as much as about 96%. This means that the lightweight blockchain scheme used in the proposed transmission method for the normal sensed data is very efficient

An XML Based Communication System for a Ubiquitous Game Simulator

There are many game simulators users can enjoy indoors. An indoor golf game simulator is a typical example of such indoor game simulators. Usually, players experience some inconvenience when they get together to use the same game console. In this paper, a communication system to support a ubiquitous game is proposed. For ubiquitous games, players do not need to get together to use the same game console. Instead, they can enjoy the game together while being in different places so long as they are playing at the same time. Because players might use different kinds of game consoles in different places, there needs to be an interoperable communication system for the games. In this paper, therefore, an XML based communication scheme is proposed and XML documents are defined to represent all the information generated by the game simulator and to process the game progress