The problem on how to determine the observability of Boolean control networks (BCNs) has been open for five years already. In this technical note, we propose a unified approach to determine all the ...four types of observability of BCNs in the literature. We define the concept of weighted pair graphs for BCNs. In the sense of each observability, we use the so-called weighted pair graph to transform a BCN to a finite automaton, and then we use the automaton to determine observability. In particular, the two types of observability that rely on initial states and inputs in the literature are determined. Finally, we show that no pairs of the four types of observability are equivalent, which reveals the essence of nonlinearity of BCNs.
The adoption of the virtual synchronous generator (VSG) has attracted wide attention because of the equivalent operating mechanism as a synchronous generator, providing a feasible scheme for the ...distributed generation connected to utility grid. However, the delivered power and frequency of the VSG may easily oscillate when the dramatic power fluctuation occurred in the distribution generation system. Fortunately, the oscillation can be damped though adjusting the rotating inertia and damping coefficient. Thus, to investigate the influences of parameters perturbation on the active power and frequency for a VSG, the small-signal model is derived and the dynamic performances are analyzed in detail. Then, based on the results of parameters analysis, an adaptive control strategy is proposed in this paper. And an optimal damping ratio can be maintained throughout the whole process of operation to suppress the oscillation of power and frequency. Therefore, the dynamic performances of the VSG are enhanced since the dynamic indexes such as the response time and overshoots are optimized. In the end, a prototype of single-phase VSG has been built and the proposed adaptive control strategy has been verified through experimental results.
This brief investigates the controllability and observability of Boolean control networks with (not necessarily bounded) time-variant delays in states. After a brief introduction to converting a ...Boolean control network to an equivalent discrete-time bilinear dynamical system via the semi-tensor product of matrices, the system is split into a finite number of subsystems (constructed forest) with no time delays by using the idea of splitting time that is proposed in this brief. Then, the controllability and observability of the system are investigated by verifying any so-called controllability constructed path and any so-called observability constructed paths in the above forest, respectively, which generalize some recent relevant results. Matrix test criteria for the controllability and observability are given. The corresponding control design algorithms based on the controllability theorems are given. We also show that the computing complexity of our algorithm is much less than that of the existing algorithms.
In this article, marine environment detection has been studied for improving the high resolution of the environment. The problem of low resolution of marine environment detection is caused by data ...synthesis defects. The supply chain management (SCM) technology is used to optimize related data to improve the resolution. The main procedure is to first preprocess the obtained hydrological data and eliminate the unreasonable amount represented by extreme values, and then the SCM method was used to estimate the results. Finally, the accuracy of the estimation is evaluated by the cross-validation algorithm. In the example verification, the comparison between the SCM method and the traditional optimal interpolation (OI) method in data integration accuracy has been done. This article compares mean square error, mean absolute error (MAE), root-mean-square error (RMSE), and
parameters. SCM provides better results than OI. Mean error (ME) = 0.6°C/month, MEA = 1.6°C/month, RMSE = 42.3°C/month, and ME and MAE values are lower in summer. It shows that it is sensitive to the lack of data and has a better ability to provide high-resolution and accurate marine environmental data in real time.
MicroRNA exhibits differential expression levels in cancer and can affect cellular transformation, carcinogenesis and metastasis. Although fluorescence techniques using dye molecule labels have been ...studied, label-free molecular-level quantification of miRNA is extremely challenging. We developed a surface plasmon resonance sensor based on two-dimensional nanomaterial of antimonene for the specific label-free detection of clinically relevant biomarkers such as miRNA-21 and miRNA-155. First-principles energetic calculations reveal that antimonene has substantially stronger interaction with ssDNA than the graphene that has been previously used in DNA molecule sensing, due to thanking for more delocalized 5s/5p orbitals in antimonene. The detection limit can reach 10 aM, which is 2.3-10,000 times higher than those of existing miRNA sensors. The combination of not-attempted-before exotic sensing material and SPR architecture represents an approach to unlocking the ultrasensitive detection of miRNA and DNA and provides a promising avenue for the early diagnosis, staging, and monitoring of cancer.
Expert finding for question answering is a challenging problem in community-based question answering (CQA) systems, arising in many real applications such as question routing and identification of ...best answers. In order to provide high-quality experts, many existing approaches learn the user model from their past question-answering activities in CQA systems. However, the past activities of users in most CQA systems are rather few, and thus the user model may not be well inferred in practice. In this paper, we consider the problem of expert finding from the viewpoint of missing value estimation. We then employ users' social networks for inferring user model, and thus improve the performance of expert finding in CQA systems. In addition, we develop a novel graph-regularized matrix completion algorithm for inferring the user model. We further develop two efficient iterative procedures, GRMC-EGM and GRMC-AGM, to solve the optimization problem. GRMC-EGM utilizes the Extended Gradient Method (EGM), while GRMC-AGM applies the Accelerated proximal Gradient search Method (AGM), for the optimization. We evaluate our methods on the well-known question answering system Quora, and the popular social network Twitter. Our empirical study shows the effectiveness of the proposed algorithms in comparison to the state-of-the-art expert finding algorithms.
White light‐emitting diodes (WLEDs) are promising next‐generation solid‐state light sources. However, the commercialization route for WLED production suffers from challenges in terms of insufficient ...color‐rendering index (CRI), color instability, and incorporation of rare‐earth elements. Herein, a new two‐component strategy is developed by assembling two broadband emissive materials with self‐trapped excitons (STEs) for high CRI and stable WLEDs. The strategy addresses effectively the challenging issues facing current WLEDs. Based on first‐principles thermodynamic calculations, copper‐based ternary halides composites, CsCu2I3@Cs3Cu2I5, are synthesized by a facile one‐step solution approach. The composites exhibit an ideal white‐light emission with a cold/warm white‐light tuning and a robust stability against heat, ultraviolet light, and environmental oxygen/moisture. A series of cold/warm tunable WLEDs is demonstrated with a maximum luminance of 145 cd m−2 and an external quantum efficiency of 0.15%, and a record high CRI of 91.6 is achieved, which is the highest value for lead‐free WLEDs. Importantly, the fabricated device demonstrates an excellent operation stability in a continuous current mode, exhibiting a long half‐lifetime of 238.5 min. The results promise the use of the hybrids of STEs‐derived broadband emissive materials for high‐performance WLEDs.
Stable and highly luminescent CsCu2I3@Cs3Cu2I5 composites are synthesized through a one‐step spin‐coating method. They exhibit white‐light emission through self‐trapped excitons, as well as cold/warm white‐light tuning. By using the composites as a white‐light emitter, electrically driven cold/warm tunable WLEDs with a record color‐rendering index of 91.6 are successfully demonstrated, and a long half‐lifetime of 238.5 min is achieved.
Mitophagy in neurological disorders Zhang, Lijun; Dai, Lei; Li, Deyuan
Journal of neuroinflammation,
12/2021, Letnik:
18, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Selective autophagy is an evolutionarily conserved mechanism that removes excess protein aggregates and damaged intracellular components. Most eukaryotic cells, including neurons, rely on proficient ...mitophagy responses to fine-tune the mitochondrial number and preserve energy metabolism. In some circumstances (such as the presence of pathogenic protein oligopolymers and protein mutations), dysfunctional mitophagy leads to nerve degeneration, with age-dependent intracellular accumulation of protein aggregates and dysfunctional organelles, leading to neurodegenerative disease. However, when pathogenic protein oligopolymers, protein mutations, stress, or injury are present, mitophagy prevents the accumulation of damaged mitochondria. Accordingly, mitophagy mediates neuroprotective effects in some forms of neurodegenerative disease (e.g., Alzheimer's disease, Parkinson's disease, Huntington's disease, and Amyotrophic lateral sclerosis) and acute brain damage (e.g., stroke, hypoxic-ischemic brain injury, epilepsy, and traumatic brain injury). The complex interplay between mitophagy and neurological disorders suggests that targeting mitophagy might be applicable for the treatment of neurodegenerative diseases and acute brain injury. However, due to the complexity of the mitophagy mechanism, mitophagy can be both harmful and beneficial, and future efforts should focus on maximizing its benefits. Here, we discuss the impact of mitophagy on neurological disorders, emphasizing the contrast between the positive and negative effects of mitophagy.
Highly corrugated graphene sheets (HCGS) have been prepared by a rapid, low cost and scalable approach through the thermal reduction of graphite oxide at 900°C followed by rapid cooling using liquid ...nitrogen. The wrinkling of the graphene sheets can significantly prevent them from agglomerating and restacking with one another face to face and thus increase the electrolyte-accessible surface area. The maximum specific capacitance of 349Fg−1 at 2mVs−1 is obtained for the HCGS electrode in 6M KOH aqueous solution. Additionally, the electrode shows excellent electrochemical stability along with an approximately 8.0% increase of the initial specific capacitance after 5000 cycle tests. These features make the present HCGS material a quite promising alternative for next generation of high-performance supercapacitors.
Batteries are gaining entry into every home and office for they are widely used because of their variant benefits. However, these batteries are prone to failure caused by charge imbalance in the ...batteries connected in either series or parallel, which can sometimes be catastrophic and hence they require to be properly monitored in a real-time manner. There exist many battery balancing schemes which are broadly grouped into either passive or active schemes. All these schemes have their own advantages and disadvantages, and hence it is upon the user to decide on which scheme will best work for them. However, research has proven that the hybrid scheme will be the best as it couples the benefits of all schemes. This study will review the various battery cell balancing methodologies and evaluate their relationship with battery performance. At present there are a few studies tackling the mechanical vibration of battery balancing performance. This study shows that battery balancing performance during long-term should be evaluated from various temperature and vibration frequencies.
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