Lignocellulosic biomass is a renewable and abundant source that can be used as a replacement for fossil resources in the sustainable production of speciality chemicals and transportation fuels. Over ...the last several decades, it has been demonstrated that one of the most effective methodology is to converse the high concentration of oxygen functionalized biomass monomers (e.g., cellulose, hemicelluloses) through de-functionalization into levulinic acid (LA) that has low oxygen content, followed by catalytic transformation of LA into fuels and valuable chemicals. This strategy currently seems to be the logical and promising alternative for sustainable development in the context of economic and environmental considerations. Besides, LA has been identified as one of the most promising platform chemicals for the sustainable production of fuels and commodity chemicals. This review is an up-to-date progress of literatures available on the subject of speciality chemicals and fuels derived from biomass through LA platform. The mechanism and current technologies for the production of LA are reviewed and compared. The potential theoretical calculation methods such as ab initio methods and density functional theories to predict the reaction pathway was also commented. The various transformation methods started from LA to speciality chemicals and fuels are critically reviewed. Among the various products, γ-valerolactone, 2-methyltetrahydrofuran and levuinate esters have been identified as promising fuels. The commercial diphenolic acid and delta-aminolevulinic acid have been widely utilized in many areas. The potential applications as well as fuel properties of these products are also discussed.
AIM To investigate the inhibitory effect of astragaloside IV on the pathological functions of cancer-associated fibroblasts,and to explore the underlying mechanism.METHODS Paired gastric normal ...fibroblast(GNF) and gastric cancer-associated fibroblast(GCAF) cultures were established from resected tissues. GCAFs were treated with vehicle control or different concentrations of astragaloside Ⅳ. Conditioned media were prepared from GNFs,GCAFs,control-treated GCAFs,and astragaloside Ⅳ-treated GCAFs,and used to culture BGC-823 human gastric cancer cells. Proliferation,migration and invasion capacities of BGC-823 cells were determined by MTT,wound healing,and Transwell invasion assays,respectively. The action mechanism of astragaloside Ⅳ was investigated by detecting the expression of micro RNAs and the expression and secretion of the oncogenic factor,macrophage colonystimulating factor(M-CSF),and the tumor suppressive factor,tissue inhibitor of metalloproteinase 2(TIMP2),in different groups of GCAFs. The expression of the oncogenic pluripotency factors SOX2 and NANOG in BGC-823 cells cultured with different conditioned media was also examined.RESULTS GCAFs displayed higher capacities to induce BGC-823 cell proliferation,migration,and invasion than GNFs(P < 0.01). Astragaloside Ⅳ treatment strongly inhibited the proliferation-,migration-and invasion-promoting capacities of GCAFs(P < 0.05 for 10 μmol/L,P < 0.01 for 20 μmol/L and 40 μmol/L). Compared with GNFs,GCAFs expressed a lower level of micro RNA-214(P < 0.01) and a higher level of micro RNA-301 a(P < 0.01). Astragaloside Ⅳ treatment significantly upregulated micro RNA-214 expression(P < 0.01) and down-regulated micro RNA-301 a expression(P < 0.01) in GCAFs. Reestablishing the micro RNA expression balance subsequently suppressed M-CSF production(P < 0.01) and secretion(P < 0.05),and elevated TIMP2 production(P < 0.01) and secretion(P < 0.05). Consequently,the ability of GCAFs to increase SOX2 and NANOG expression in BGC-823 cells was abolished by astragaloside Ⅳ.CONCLUSION Astragaloside Ⅳ can inhibit the pathological functions of GCAFs by correcting their dysregulation of micro RNA expression,and it is promisingly a potent therapeutic agent regulating tumor microenvironment.
Gliomas are the commonest and most aggressive primary malignant tumor in the central nervous system. Long noncoding RNAs (lncRNAs) have been identified to act as crucial regulators in multiple ...biological processes, including tumorigenesis. FAM83H antisense RNA1 (FAM83H‐AS1) has been uncovered to be dysregulated in several cancers. However, the biological role of FAM83H‐AS1 in glioma still needs to be investigated. Currently, our findings indicated that FAM83H‐AS1 was upregulated in glioma tissues and cell lines and high level of FAM83H‐AS1 was associated with poor prognosis of glioma. Loss‐of‐function assays demonstrated that silenced FAM83H‐AS1 obviously suppressed cell proliferation via regulating the cell‐cycle distribution and cell apoptosis rate, and mechanistic experiments revealed that FAM83H‐AS1 could epidemically silence CDKN1A expression through recruiting EZH2 to the promoter of CDKN1A, thereby influencing the cell cycle and proliferation. Collectively, our findings suggested that FAM83H‐AS1 participated in the progression of glioma and might act as a potential therapeutic target and prognosis biomarker for human glioma.
FAM83H‐AS1 participated in the progression of glioma and might act a potential therapeutic target and prognosis biomarker for human glioma.
Studies of human mobility in the past decade revealed a number of general scaling laws. However, to reproduce the scaling behaviors quantitatively at both the individual and population levels ...simultaneously remains to be an outstanding problem. Moreover, recent evidence suggests that spatial scales have a significant effect on human mobility, raising the need for formulating a universal model suited for human mobility at different levels and spatial scales. Here we develop a general model by combining memory effect and population-induced competition to enable accurate prediction of human mobility based on population distribution only. A variety of individual and collective mobility patterns such as scaling behaviors and trajectory motifs are accurately predicted for different countries and cities of diverse spatial scales. Our model establishes a universal underlying mechanism capable of explaining a variety of human mobility behaviors, and has significant applications for understanding many dynamical processes associated with human mobility.
This article focuses on the robust fault tolerant control (FTC) problem for a class of Lipschitz nonlinear multi‐agent systems(MASs) subject to sensor faults. Firstly, sensor faults are transformed ...into actuator faults via introducing a new intermediate auxiliary state variable, and a distributed adaptive fault estimation observer is designed to estimate the state information and the concerned faults by using the relative output estimation error. Then, the sufficient existence conditions for the observer to satisfy the robust performance index are given. Thirdly, based on the results of observer design, a new design method of dynamic output feedback controller is proposed to implement consensus of MASs and ensure the desired disturbance rejection performance. Finally, the simulation results are presented to illustrate the effectiveness of the proposed method.
Finger vein patterns recognition as a new type of biometric recognition technology, the existing pattern of the finger vein recognition has registered and verified the disadvantage of slow speed. ...Therefore, in this paper, a finger vein feature extraction and matching recognition algorithm suitable for FPGA is proposed, and the hardware system of finger vein recognition is designed and implemented, including three modules: finger vein image acquisition device, image processing module and matching display module. Finally, the key algorithm is simulated and analyzed. It speeds up the registration and recognition of mobile phone veins.
Group‐10 transition metal dichalcogenides (TMDs) with distinct optical and tunable electrical properties have exhibited great potential for various optoelectronic applications. Herein, a self‐powered ...photodetector is developed with broadband response ranging from deep ultraviolet to near‐infrared by combining FA1−xCsxPbI3 perovskite with PdSe2 layer, a newly discovered TMDs material. Optoelectronic characterization reveals that the as‐assembled PdSe2/perovskite Schottky junction is sensitive to light illumination ranging from 200 to 1550 nm, with the highest sensitivity centered at ≈800 nm. The device also shows a large on/off ratio of ≈104, a high responsivity (R) of 313 mA W−1, a decent specific detectivity (D*) of ≈1013 Jones, and a rapid response speed of 3.5/4 µs. These figures of merit are comparable with or much better than most of the previously reported perovskite detectors. In addition, the PdSe2/perovskite device exhibits obvious sensitivity to polarized light, with a polarization sensitivity of 6.04. Finally, the PdSe2/perovskite detector can readily record five “P,” “O,” “L,” “Y,” and “U” images sequentially produced by 808 nm. These results suggest that the present PdSe2/perovskite Schottky junction photodetectors may be useful for assembly of optoelectronic system applications in near future.
A large‐area, highly polarization‐sensitive and broadband photodetector based on multilayered PdSe2/perovskite device is demonstrated. From optoelectronic characterization, the device achieves an impressive specific detectivity of ≈1013 Jones, a polarization sensitivity as high as 6.04, and a fast response speed of 3.5/4 µs. Further study reveals that the present device is potentially important for image sensor applications.
With the development of artificial intelligence, autonomous learning writing robot has been a hot research topic. In this paper, the development of using cheap chip design suitable for low-end market ...need to write the low cost of robots, solve the traditional writing robot based on vision is higher requirements for image processing cost the problem. RBF neural network was optimized to learn and classify the pre-processed eigenvalues in the classifier, and its parallel broadcasting ability in Arduino 101 development board was used to make it learn, which improved the recognition rate and the performance of the writing robot.
The mammalian target of rapamycin (mTOR) pathway plays critical roles in intrinsic chemoresistance by regulating Fanconi anaemia complementation group D2 (FANCD2) expression. However, the mechanisms ...by which mTOR regulates FANCD2 expression and related inhibitors are not clearly elucidated. Extracts of Centipeda minima (C. minima) showed promising chemosensitizing effects by inhibiting FANCD2 activity. Here, we have aimed to identify the bioactive chemosensitizer in C. minima extracts and elucidate its underlying mechanism.
The chemosensitizing effects of arnicolide C (ArC), a bioactive compound in C. minima, on non-small cell lung cancer (NSCLC) were investigated using immunoblotting, immunofluorescence, flow cytometry, the comet assay, small interfering RNA (siRNA) transfection and animal models. The online SynergyFinder software was used to determine the synergistic effects of ArC and chemotherapeutic drugs on NSCLC cells.
ArC had synergistic cytotoxic effects with DNA cross-linking drugs such as cisplatin and mitomycin C in NSCLC cells. ArC treatment markedly decreased FANCD2 expression in NSCLC cells, thus attenuating cisplatin-induced FANCD2 nuclear foci formation, leading to DNA damage and apoptosis. ArC inhibited the mTOR pathway and attenuated mTOR-mediated expression of E2F1, a critical transcription factor of FANCD2. Co-administration of ArC and cisplatin exerted synergistic anticancer effects in the A549 xenograft mouse model by suppressing mTOR/FANCD2 signalling in tumour tissues.
ArC suppressed DNA cross-linking drug-induced DNA damage response by inhibiting the mTOR/E2F1/FANCD2 signalling axis, serving as a chemosensitizing agent. This provides insight into the anticancer mechanisms of ArC and offers a potential combinatorial anticancer therapeutic strategy.
Nature is capable of storing solar energy in chemical bonds via photosynthesis through a series of C-C, C-O and C-N bond-forming reactions starting from CO
and light. Direct capture of solar energy ...for organic synthesis is a promising approach. Lead (Pb)-halide perovskite solar cells reach 24.2% power conversion efficiency, rendering perovskite a unique type material for solar energy capture. We argue that photophysical properties of perovskites already proved for photovoltaics, also should be of interest in photoredox organic synthesis. Because the key aspects of these two applications are both relying on charge separation and transfer. Here we demonstrated that perovskites nanocrystals are exceptional candidates as photocatalysts for fundamental organic reactions, for example C-C, C-N and C-O bond-formations. Stability of CsPbBr
in organic solvents and ease-of-tuning their bandedges garner perovskite a wider scope of organic substrate activations. Our low-cost, easy-to-process, highly-efficient, air-tolerant and bandedge-tunable perovskites may bring new breakthrough in organic chemistry.
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