57 research outputs found
Pharmacokinetic, acute toxicity, and pharmacodynamic studies of semen strychni total alkaloid microcapsules
Purpose: To investigate the safety and effectiveness of semen strychni total alkaloid microcapsules (SSTAM), compared with semen strychni total alkaloids (SSTA).
Methods: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed to assess pharmacokinetics of brucine and strychnine in rats. Acute toxicity was investigated in pre-test and formal experiments in mice. The pharmacodynamics of SSTAM and SSTA were evaluated by their analgesic and anti-inflammatory activities.
Results: With respect to brucine, the half-life of SSTA group (1.6 mg/kg), low-dose SSTAM group (6 mg/kg) and high-dose SSTAM group (10 mg/kg) was 5.723, 9.321 and 9.025 h, respectively. With respect to strychnine, the half-life of SSTA group, low-dose SSTAM group and high-dose SSTAM group was 4.065, 8.819 and 8.654 h, respectively. The LD50 values of SSTAM group and SSTA group were 236.59 and 30.27 mg/kg, respectively. The pain inhibition rates of SSTAM groups (25 and 50 mg/kg) were higher than that of SSTA group (p < 0.05) while the pain threshold values of the SSTAM groups (25 and 50 mg/kg) were higher than that of blank control (p < 0.01) and SSTA groups (p < 0.01) at 60 min and 120 min. The inhibition rates of the SSTAM groups (25 and 50 mg/kg) were higher than that of SSTA group based on ear swelling and cotton ball granulation tests. Compared with blank control and SSTA groups, the absorbance values of SSTAM groups (25 and 50 mg/kg) were lower (p < 0.01).
Conclusion: SSTAM increases the dosage of administration but reducea the toxicity of the alkaloids in rats, and is thus a potentially safe and effective drug delivery system
A Large-scale Benchmark for Log Parsing
Log data is pivotal in activities like anomaly detection and failure
diagnosis in the automated maintenance of software systems. Due to their
unstructured format, log parsing is often required to transform them into a
structured format for automated analysis. A variety of log parsers exist,
making it vital to benchmark these tools to comprehend their features and
performance. However, existing datasets for log parsing are limited in terms of
scale and representativeness, posing challenges for studies that aim to
evaluate or develop log parsers. This problem becomes more pronounced when
these parsers are evaluated for production use. To address these issues, we
introduce a new collection of large-scale annotated log datasets, named LogPub,
which more accurately mirrors log data observed in real-world software systems.
LogPub comprises 14 datasets, each averaging 3.6 million log lines. Utilizing
LogPub, we re-evaluate 15 log parsers in a more rigorous and practical setting.
We also propose a new evaluation metric to lessen the sensitivity of current
metrics to imbalanced data distribution. Furthermore, we are the first to
scrutinize the detailed performance of log parsers on logs that represent rare
system events and offer comprehensive information for system troubleshooting.
Parsing such logs accurately is vital yet challenging. We believe that our work
could shed light on the design and evaluation of log parsers in more realistic
settings, thereby facilitating their implementation in production systems
The relationship between triglyceride, cholesterol and lipoprotein levels, and immune responses to hepatitis B vaccine
Cholesterol homeostasis disorder and hypertriglyceridemia, as common metabolic conditions, have rarely been reported to affect the immune responses to the hepatitis B vaccine. Our study found that higher high-density lipoprotein (HDL) level showed a significant relationship with positive anti-HBs results (cOR = 1.479, 95% CI: 1.150, 1.901, p = 0.002; aOR = 1.304, 95% CI: 1.006, 1.691, p = 0.045), especially in individuals aged 18- to 40-year-old, female, smoking more than 100 cigarettes in life, and drinking more than 12 times every year. Lower low-density lipoprotein (LDL) level was associated with a negative anti-HBs result among participants aged 18- to 40-year-old, and participants who were obese. Higher level of HDL and lower level of LDL may be protective factors of better immune effect of hepatitis B vaccine. More research should be conducted to investigate the influence of the cholesterol level on the immune responses to the hepatitis B vaccine, and more in-depth research should be performed to uncover the mechanism
SHP-2 Promotes the Maturation of Oligodendrocyte Precursor Cells Through Akt and ERK1/2 Signaling In Vitro
Background: Oligodendrocyte precursor cells (OPCs) differentiate into oligodendrocytes (OLs), which are responsible for myelination. Myelin is essential for saltatory nerve conduction in the vertebrate nervous system. However, the molecular mechanisms of maturation and myelination by oligodendrocytes remain elusive. Methods and Findings: In the present study, we showed that maturation of oligodendrocytes was attenuated by sodium orthovanadate (a comprehensive inhibitor of tyrosine phosphatases) and PTPi IV (a specific inhibitor of SHP-2). It is also found that SHP-2 was persistently expressed during maturation process of OPCs. Down-regulation of endogenous SHP-2 led to impairment of oligodendrocytes maturation and this effect was triiodo-L-thyronine (T3) dependent. Furthermore, overexpression of SHP-2 was shown to promote maturation of oligodendrocytes. Finally, it has been identified that SHP-2 was involved in activation of Akt and extracellular-regulated kinases 1 and 2 (ERK1/2) induced by T3 in oligodendrocytes
Energy efficiency of wireless network using coordinated gated narrow beams
© 2019 Dr. Jiazhen ZhuWith the ever-increasing demand for wireless service and higher data rate, the wireless network has experienced an unprecedented growth worldwide in the past decade and it is expected to grow continuously. Energy efficiency of the wireless network has become a growing concern for network operators and standardization authorities, not only to reduce the overall electric energy usage but also to reduce its environmental footprint. This has triggered research work to explore future, green wireless technologies and strategies in order to bring energy efficiency improvements in the entire network.
In this thesis, we investigate the opportunity of improving energy efficiency through the use of coordinated gated narrow beams for downlink transmission of data. This is a class of Coordinated Multipoint (CoMP) transmission technique which is originally proposed in LTE standards for enhancing cell-edge throughput. The principle is that multiple base stations are coordinated with each other so that potential interfering source from the adjacent base station can be steered away by appropriate beamforming and scheduling.
The thesis is divided into three parts. In the first part, we develop a realistic coordinated beamforming strategy using gated narrow beams and estimate the network throughput and base station power consumption based on network level simulation. In the simulator, we apply a practical traffic model in which users entering at a rate consistent with time of day dependent traffic level, and a proportional fair resource scheduling scheme to ensure fairness between users. Then, we analyse the required channel state information to support the beam coordination and resource scheduling, and develop a low-overhead signalling and control framework that provides sufficient signalling information. The signalling design and its implementation leverage signalling functionality and protocol in current standards. We develop methodologies for quantifying the signalling overheads introduced in terms of the percentage of downlink resource occupied by additional coordination reference signals.
Finally, we develop energy consumption models of the functional components and processes in the coordinated network architecture, including backhaul switches and interfaces, and a central coordination unit. We quantify the additional energy costs associated with the coordination and signalling functions, and perform a comprehensive evaluation on the energy efficiency of an LTE network employing the proposed coordinated gated narrow beams. Our results show that significant energy savings can be achieved compared with a conventional network with no coordination
Competition and diffusion of two species on a growing domain
This paper is concerned with a Lotka-Volterra competition model with diffusion on a growing domain. We establish a threshold type result on the global dynamics by the virtue of reproduction index. Our theoretical results, together with the numerical simulations, reveal that the expansion of living area benefits the long-term persistence of competitive populations for both sides
Zero-Carbon Communities: Research Hotspots, Evolution, and Prospects
Global warming is a worldwide concern, with buildings generating more than 40% of the annual global CO2 emissions. A commonly accepted system of global standards for zero-carbon buildings and communities has not yet been established. In this research, the development history, hotspots, and trends at the urban scale with theoretical and data support are summarized based on the Web of Science (WoS) Core Collection. The review contains works from 1997 to 2022. A total of 19,014 papers were collected, with an overall increasing trend in the number of articles with specific keywords. The scope of the research is broad, covering the environment, sciences, ecology, chemistry, material science, physics, meteorology, atmospheric sciences, and so on. The hotspots in the low-carbon community (LCC) and zero-carbon community (ZCC) involve a wide range of disciplines, and collaborative research between related disciplines should be strengthened to propose practical solutions for the development of zero-carbon cities. The establishment of the ZCC mainly focuses on a zero-carbon-emission construction and zero-carbon operations. This research found approaches such as the choices of building construction and material, a waste recycling system, a regenerating energy system, transportation, and an examination of the community composition to realize the ZCC. In the literature it is presented that the difficulties in the construction of the ZCC are due to the lack of research in practice, operation, and subsequent maintenance. Moreover, other scholars can deepen the research on the hotspots of ZCC
Sustainable co-governance of smart bike-sharing schemes based on consumers' perspective
Smart bike-sharing Schemes (Smart BSSs) have gained much attention with the tide of sharing economy. The unprecedented development of Smart BSSs results in considerable socioeconomic and environmental benefits but also creates new urban governance issues. Previous studies have mostly explored from the perspective of policy and market, but few literature tried to analyze the relationship between different stakeholders and their influence factors from the perspective of consumers. Therefore, the latter will be the focus of this study. 2095 valid online questionnaires were collected through online data collection platform and social media. Conceptual framework, Variable set, descriptive statistics, correlation and regression analysis methods were designed step by step. Study results showed that the consumers’ willingness to participate in co-governance of Smart BSSs is significant and the influence factors presented the diverse characteristics. Finally, this study provided the multi-path solutions for the further co-government. For consumers, positive participation in co-governance of Smart BSSs; For the government and urban managers, it is necessary to constantly optimize related institutional arrangements; For Smart BSSs enterprises, how to adopt rational market behaviors and improve service level will become the key. The study, one the one hand, is devoted to contribute important empirical materials for the in-depth discussion of sharing economy, on the other hand, will provide potential route choices for the further optimization of institutional arrangements in co-governance of Smart BSSs in the future
Undesirable factors in integer-valued DEA : evaluating the operational efficiencies of city bus systems considering safety records
In conventional data envelopment analysis (DEA) methods, all inputs and outputs are assumed to be continuous. However, in many practical situations, firms may generate both desirable and undesirable outputs, and some of which may only take integer values (e.g., the number of traffic accidents and deaths in a transportation system). The efficiency evaluation results can be inaccurate if these conditions are not incorporated in the model. In this paper we propose an integer DEA model with undesirable inputs and outputs. The proposed model is developed based on the additive DEA model, in which input and output slacks are used to compute efficiency scores. We also develop an integer super-efficiency model to discriminate the performance of efficient firms. As an illustration, we apply the proposed models to the longitudinal data from a city bus company in Taiwan
- …