In the clinic, the wheezing sound is usually considered as an indicator symptom to reflect the degree of airway obstruction. The auscultation approach is the most common way to diagnose wheezing sounds, but it subjectively depends on the experience of the physician. Several previous studies attempted to extract the features of breathing sounds to detect wheezing sounds automatically. However, there is still a lack of suitable monitoring systems for real-time wheeze detection in daily life. In this study, a wearable and wireless breathing sound monitoring system for real-time wheeze detection was proposed. Moreover, a breathing sounds analysis algorithm was designed to continuously extract and analyze the features of breathing sounds to provide the objectively quantitative information of breathing sounds to professional physicians. Here, normalized spectral integration (NSI) was also designed and applied in wheeze detection. The proposed algorithm required only short-term data of breathing sounds and lower computational complexity to perform real-time wheeze detection, and is suitable to be implemented in a commercial portable device, which contains relatively low computing power and memory. From the experimental results, the proposed system could provide good performance on wheeze detection exactly and might be a useful assisting tool for analysis of breathing sounds in clinical diagnosis.

Prostate cancer (PCa) is one of the most prevalent male cancers in western world. Radiation therapy (RT) is commonly used to treat PCa patients. However, a certain proportion of patients develop radioresistant PCa cells, which results in metastatic disease. Statins, which inhibit 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase, are commonly used to treat hypercholesterolemia, exhibiting beneficial effects on cardiovascular diseases and on several types of cancers, including PCa. However, the mechanistic details and crosstalk between statins and RT in PCa cells remain unknown. In this study, radioresistant DOC-2/DAB2 interactive protein (DAB2IP)-deficient PCa cells were used to evaluate whether simvastatin could enhance the effect of ionizing radiation (IR). The crucial molecules that associated with simvastatin elevated radiosensitivity in PCa cells were explored. Our results demonstrated that a combination treatment with simvastatin and IR synergistically induced apoptosis of radioresistant PCa cells. In addition, simvastatin appeared to compromise DNA double-strand breaks repair by activating the expressions of histone 2A family member X (γ-H2AX) and phospho-checkpoint kinase 1 (p-CHK1), suggesting an underlying mechanism for this radiosensitization of PCa cells. These findings reveal that simvastatin may be a potent therapeutic agent for co-treatment with radiation to overcome radioresistance in PCa cells.

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The degradation behavior of the Ti/HfO x bipolar resistive random access memory (RRAM) during endurance cycles, and the operational parameters, which induce the endurance failure, are studied through the two proposed stressing methods. The over-RESET energy is considered to be the key electrical parameter to induce endurance failure in the memory device. When the device suffers the over-RESET energy, a gradually reduced memory window is observed associated with endurance cycles, and the overall degradation will include two stages. The first stage can be explained by the worn filament model and is mainly due to imbalance energy between SET and RESET process. The occurrence of unusual resistance-voltage (R-V) patterns at positive and negative voltage seep in the memory device under the second stage degradation demonstrates the existence of complementary resistive switching (CRS) in the single Ti/HfO x bipolar RRAM. After analyzing the operation conditions to activate the self-CRS in memory device with one transistor-one resistor (1T-1R) configuration, the mechanism about the second stage degradation in the RRAM originated from over-RESET energy is also discussed. A mechanism based on the worn filament model and the induction of CRS is proposed to explain the endurance failure induced by over-RESET in the Ti/HfO x RRAM with 1T-1R configuration. With an appropriate RESET energy, a robust reliability for endurance cycles is expected.