Research on active sound absorption based on minimality of quadratic sum of reflected sound pressure in low frequency

In this paper, the minimality of the quadratic sum of the reflected sound pressure is used to outline the method of active sound absorption. A piezoelectric ceramic is attached to a simply supported plate, and two microphones are placed in the front of the simply supported plate. The reflected sound pressure is measured. According to the measured reflected sound pressure, the voltage is added to the surface of the piezoelectric ceramic. Then, the simply supported plate is vibrated. Thus, the total sound pressure is expressed as a combination of the reflected sound pressure and the radiated sound pressure. A condition of the quadratic sum being minimal is presented and the voltage (added to the surface of the piezoelectric ceramic) is calculated. At last, the numerical calculation and the experiment are carried out, which demonstrate that the method outlined in this paper is possible

Static compression regulates OPG expression in periodontal ligament cells via the CAMK II pathway

Objective This study aimed to investigate the potential role of CAMK II pathway in the compression-regulated OPG expression in periodontal ligament cells (PDLCs). Material and Methods The PDL tissue model was developed by 3-D culturing human PDLCs in a thin sheet of poly lactic-co-glycolic acid (PLGA) scaffolds, which was subjected to static compression of 25 g/cm2 for 3, 6 and 12 h, with or without treatment of KN-93. After that, the expression of OPG, RANKL and NFATC2 was investigated through real-time PCR and western blot analysis. Results After static compression, the NFATC2 and RANKL expression was significantly up-regulated, while partially suppressed by KN-93 for 6 and 12 h respectively. The OPG expression was significantly down-regulated by compression in 3 h, started to elevate in 6 h, and significantly up-regulated in 12 h. The up-regulation after 12 h was significantly suppressed by KN-93. Conclusions Long-term static compression increases OPG expression in PDLCs, at least partially, via the CAMK II pathway

BlockEmulator: An Emulator Enabling to Test Blockchain Sharding Protocols

Numerous blockchain simulators have been proposed to allow researchers to simulate mainstream blockchains. However, we have not yet found a testbed that enables researchers to develop and evaluate their new consensus algorithms or new protocols for blockchain sharding systems. To fill this gap, we develop BlockEmulator, which is designed as an experimental platform, particularly for emulating blockchain sharding mechanisms. BlockEmulator adopts a lightweight blockchain architecture such that developers can only focus on implementing their new protocols or mechanisms. Using layered modules and useful programming interfaces offered by BlockEmulator, researchers can implement a new protocol with minimum effort. Through experiments, we test various functionalities of BlockEmulator in two steps. Firstly, we prove the correctness of the emulation results yielded by BlockEmulator by comparing the theoretical analysis with the observed experiment results. Secondly, other experimental results demonstrate that BlockEmulator can facilitate the measurement of a series of metrics, including throughput, transaction confirmation latency, cross-shard transaction ratio, the queuing size of transaction pools, workload distribution across blockchain shards, etc. We have made BlockEmulator open-source in Github

White Matter Injury After Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (ICH) accounts for 15% of all stroke cases. ICH is a devastating form of stroke associated with high morbidity, mortality, and disability. Preclinical studies have explored the mechanisms of neuronal death and gray matter damage after ICH. However, few studies have examined the development of white matter injury (WMI) following ICH. Research on WMI indicates that its pathophysiological presentation involves axonal damage, demyelination, and mature oligodendrocyte loss. However, the detailed relationship and mechanism between WMI and ICH remain unclear. Studies of other acute brain insults have indicated that WMI is strongly correlated with cognitive deficits, neurological deficits, and depression. The degree of WMI determines the short- and long-term prognosis of patients with ICH. This review demonstrates the structure and functions of the white matter in the healthy brain and discusses the pathophysiological mechanism of WMI following ICH. Our review reveals that the development of WMI after ICH is complex; therefore, comprehensive treatment is essential. Understanding the relationship between WMI and other brain cells may reveal therapeutic targets for the treatment of ICH

Static compression regulates OPG expression in periodontal ligament cells via the CAMK II pathway

ABSTRACT Objective This study aimed to investigate the potential role of CAMK II pathway in the compression-regulated OPG expression in periodontal ligament cells (PDLCs). Material and Methods The PDL tissue model was developed by 3-D culturing human PDLCs in a thin sheet of poly lactic-co-glycolic acid (PLGA) scaffolds, which was subjected to static compression of 25 g/cm2 for 3, 6 and 12 h, with or without treatment of KN-93. After that, the expression of OPG, RANKL and NFATC2 was investigated through real-time PCR and western blot analysis. Results After static compression, the NFATC2 and RANKL expression was significantly up-regulated, while partially suppressed by KN-93 for 6 and 12 h respectively. The OPG expression was significantly down-regulated by compression in 3 h, started to elevate in 6 h, and significantly up-regulated in 12 h. The up-regulation after 12 h was significantly suppressed by KN-93. Conclusions Long-term static compression increases OPG expression in PDLCs, at least partially, via the CAMK II pathway