This article deals with strong structural controllability of linear systems. In contrast to the existing work, the structured systems studied in this article have a so-called zero/nonzero/arbitrary ...structure, which means that some of the entries are equal to zero, some of the entries are arbitrary but nonzero, and the remaining entries are arbitrary (zero or nonzero). We formalize this in terms of pattern matrices, whose entries are either fixed zero, arbitrary nonzero, or arbitrary. We establish necessary and sufficient algebraic conditions for strong structural controllability in terms of full rank tests of certain pattern matrices. We also give a necessary and sufficient graph-theoretic condition for the full rank property of a given pattern matrix. This graph-theoretic condition makes use of a new color change rule that is introduced in this article. Based on these two results, we then establish a necessary and sufficient graph-theoretic condition for strong structural controllability. Moreover, we relate our results to those that exist in the literature and explain how our results generalize previous work.
The downward shortwave radiation (DSR) is an important part of the Earth’s energy balance, driving Earth’s system’s energy, water, and carbon cycles. Due to the harsh Antarctic environment, the ...accuracy of DSR derived from satellite and reanalysis has not been systematically evaluated over the transect of Zhongshan station to Dome A, East Antarctica. Therefore, this study aims to evaluate DSR reanalysis products (ERA5-Land, ERA5, MERRA-2) and satellite products (CERES and ICDR) in this area. The results indicate that DSR exhibits obvious monthly and seasonal variations, with higher values in summer than in winter. The ERA5-Land (ICDR) DSR product demonstrated the highest (lowest) accuracy, as evidenced by a correlation coefficient of 0.988 (0.918), a root-mean-square error of 23.919 (69.383) W m
−2
, a mean bias of −1.667 (−28.223) W m
−2
and a mean absolute error of 13.37 (58.99) W m
−2
. The RMSE values for the ERA5-Land reanalysis product at seven stations, namely Zhongshan, Panda 100, Panda 300, Panda 400, Taishan, Panda 1100, and Kunlun, were 30.938, 29.447, 34.507, 29.110, 20.339, 17.267, and 14.700 W m
−2
, respectively; with corresponding bias values of 9.887, −12.159, −19.181, −15.519, −8.118, 6.297, and 3.482 W m
−2
. Regarding seasonality, ERA5-Land, ERA5, and MERRA-2 reanalysis products demonstrate higher accuracies during spring and summer, while ICDR products are least accurate in autumn. Cloud cover, water vapor, total ozone, and severe weather are the main factors affecting DSR. The error of DSR products is greatest in coastal areas (particularly at the Zhongshan station) and decreases towards the inland areas of Antarctica.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A magnetic ionic liquid (abridged as MIL) C
6
mim
5
Dy(SCN)
8
was prepared and used as the magnetic lubricant of a steel-steel sliding pair. The tribological properties of the as-prepared MIL were ...evaluated with a commercially obtained magnetic fluid lubricant (abridged as MF; the mixture of dioctyl sebacate and Fe
3
O
4
, denoted as DIOS-Fe
3
O
4
) as a control. The lubrication mechanisms of the two types of magnetic lubricants were discussed in relation to worn surface analyses by SEM-EDS, XPS, and profilometry, as well as measurement of the electric contact resistance of the rubbed steel surfaces. The results revealed that the MIL exhibits better friction-reducing and antiwear performances than the as-received MF under varying test temperatures and loads. This is because the MIL participates in tribochemical reactions during the sliding process, and forms a boundary lubrication film composed of Dy
2
O
3
, FeS, FeSO
4
, nitrogen-containing organics, and thioether on the rubbed disk surface, thereby reducing the friction and wear of the frictional pair. However, the MF is unable to form a lubricating film on the surface of the rubbed steel at 25 °C, though it can form a boundary film consisting of Fe
3
O
4
and a small amount of organics under high temperature. Furthermore, the excessive Fe
3
O
4
particulates that accumulate in the sliding zone may lead to enhanced abrasive wear of the sliding pair.
The agitation of BaTiO
3
via
ball milling converts mechanical energy into electrical energy, leading to the reduction of molecular oxygen
via
a single electron transfer pathway analogous to the ...photocatalytic reaction. This mechanoredox strategy for the oxidative coupling of thiols could eliminate waste and develop a recyclable methodology to accomplish organic transformations in a greener fashion, exhibiting promising potential for large-scale chemical manufacturing.
The agitation of BaTiO
3
via
ball milling converts mechanical energy into electrical energy, leading to the reduction of molecular oxygen
via
a single electron transfer pathway analogous to the photocatalytic reaction.
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IJS, KILJ, NUK, UL, UM, UPUK
Nonsteroidal anti-inflammatory drugs (NSAIDs) combined with chemotherapeutic agents for the treatment of colorectal cancer (CRC) are a promising therapeutic strategy. NSAIDs can effectively boost the ...antitumor efficacy of chemotherapeutic agents by inhibiting the synthesis of COX-2. However, hazardous side effects and barriers to oral drug absorption are the main challenges for combination therapy with chemotherapeutics and NSAIDs. To address these issues, a safe and effective lysine–polydopamine@abemaciclib-flurbiprofen (Flu) codrug nanocrystal (Lys-PDA@AF NCs) was designed. Abemaciclib (Abe), a novel and effective inhibitor of the CDK4/6 enzyme, and Flu were joined to prepare Abemaciclib-Flu codrug (AF) by amide bonds, and then the AF was made into nanocrystals. Lysine-modified polydopamine was selected as a shell to encapsulate nanocrystals to enhance intestinal adhesion and penetration and lengthen the duration time of drugs in vivo. Nuclear magnetic resonance, Fourier transform infrared, Massspectrometry, X-ray photoelectron spectroscopy, Transmission electron microscopy, and drug loading were used to evaluate the physicochemical characteristics of the nanocrystals. In our study, Abe and Flu were released to exert their synergistic effect when the amide bond of AF was broken and the amide bond was sensitive to cathepsin B which is overexpressed in most tumor tissues, thus increasing the selectivity of the drug to the tumor. The results showed that Lys-PDA@AF NCs had higher cytotoxicity for CRC cell with an IC50 of 4.86 μg/mL. Additionally, pharmacokinetics showed that Abe and Flu had similar absorption rates in the Lys-PDA@AF NCs group, improving the safety of combination therapy. Meanwhile, in vivo experiments showed that Lys-PDA@AF NCs had excellent antitumor effects and safety. Overall, it was anticipated that the created Lys-PDA@AF NCs would be a potential method for treating cancer.
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IJS, KILJ, NUK, PNG, UL, UM, UPUK
•We studied the effects of honey processing on nitrofuran levels.•We described an environment-friendly method that can remove nitrofurans from honey.•LS-901 resin was selected as the optimal resin ...for removing nitrofurans from honey.•Resin-treated honey can be safely used as winter feed for honeybees.
There is increasing concern that the presence of antibiotics such as nitrofurans in animal-derived food products is harmful to human. This study originally assessed the effects of different honey processing steps on the stabilities of four nitrofuran metabolites (3-amino-2-oxazolidone, 1-aminohydantonin, semicarbazide and 3-amino-5-morpholinomethyl-2-oxazolidone). Macroporous adsorption resins (MARs) were evaluated for the removal of these residues. Nitrofuran metabolites were analysed by LC–MS/MS after each processing step. The results revealed that honey processing reduced nitrofuran metabolites in honey and the total loss was from 56.6% to 90.4%. Furthermore, LS-901 was the optimum MAR with adsorption rates of 69.9–91.8% for four metabolites. After removing nitrofuran metabolites, the honey could be safely used as winter feed for honeybees.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A facile microwave-assisted hydrothermal route has been developed for a synthesis of versatile carbon materials. The monosaccharide fructose aqueous solution was adopted as the starting material, and ...the p H of the solution was adjusted to be in acidic（pH 4）, neutral（pH 7） and basic（pH 10.5） conditions. The p H buffered fructose solutions were treated at different temperatures by a microwave-assisted hydrothermal technique. As-prepared carbon materials displayed p H and temperature dependent multi-morphologies（porous, spherical or core-shell）, which were determined by transmission and scanning electron microscopic analyses（TEM and SEM）. And the hypothesis of dehydration mechanism of hydrothermal synthesis was analyzed by ultraviolet extinction and Fourier transform infrared spectroscopy. It was found that as compared with normal hydrothermal synthesis, microwave assistance could efficiently increase the production yield and improve the spherical geometry of the carbon particles in neutral condition. By changing the p H of the system, acidic p H induces aggregation of the spheres, while basic p H produces more trends toward core-shell or sponge-like porous structure. The study opens a novel route to the production of polytropic carbon materials and suggests a potential niche market established from the green synthesis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper presents a neural-network-based boundary control method for a gantry system with unknown friction and output constraint. Firstly, to tackle the unknown friction, a radial basis function ...neural network (RBFNN) is adopted to approximate it. Secondly, we employ a barrier Lyapunov function to handle the output constraint problem. Then, a neural-network-based boundary controller is proposed to deal with the aforementioned problems. Subsequently, based on the Lyapunov stability approach, the uniformly ultimately bounded stability of the state of the closed-loop system is guaranteed. Finally, the effectiveness of the developed control method is illustrated through both numerical simulations and physical experiments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper focuses on the stability and sliding mode issues for the two-dimensional (2D) Fornasini-Marchesini (FMII) networked control system under packet dropouts. Firstly, the output-based 2D ...event-triggered strategy was constructed to alleviate information transmission pressure caused by limited network resources. Secondly, by considering the impact of packet dropouts, we propose an output-based 2D sliding mode controller and formulate the output-based 2D error-estimation scheme accordingly. Moreover, to get rid of the nonlinear coupling of the conditions (to guarantee the mean-square stability), we established an adaptive intelligence algorithm. Finally, we provide a numerical example to verify the effectiveness and practicability of the proposed algorithm and controller design.
The gut microecological network is a complex microbial community within the human body that plays a key role in linking dietary nutrition and host physiology. To understand the complex relationships ...among microbes and their functions within this community, network analysis has emerged as a powerful tool. By representing the interactions between microbes and their associated omics data as a network, we can gain a comprehensive understanding of the ecological mechanisms that drive the human gut microbiota. In addition, the network-based approach provides a more intuitive analysis of the gut microbiota, simplifying the study of its complex dynamics and interdependencies. This review provides a comprehensive overview of the methods used to construct and analyze networks in the context of gut microecological background. We discuss various types of network modeling approaches, including co-occurrence networks, causal networks, dynamic networks, and multi-omics networks, and describe the analytical techniques used to identify important network properties. We also highlight the challenges and limitations of network modeling in this area, such as data scarcity and heterogeneity, and provide future research directions to overcome these limitations. By exploring these network-based methods, researchers can gain valuable insights into the intricate relationships and functional roles of microbial communities within the gut, ultimately advancing our understanding of the gut microbiota's impact on human health.
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