•This review presents naturally occurring polysaccharides with anti-diabetic activities.•Polysaccharides alleviate β-cell dysfunction through antiinflammatory and/or antioxidative effects and ...increase insulin secretion.•Polysaccharides inhibit α-amylase and α-glucosidase activities and improve glucose metabolism.•Polysaccharides exhibit insulin-sensitizing potentials.
Type 2 diabetes mellitus, a common metabolic and endocrine disorder worldwide, causes severe health and economic problems. At present, pharmacotherapy involving synthetic diabetic agents is clinically administered for diabetic therapy, which has certain side effects. Fortunately, various natural polysaccharides have anti-diabetic activity and use of these polysaccharides as adjuncts to conventional therapies is increasing in developing countries. A literature search was conducted to obtain relevant information of anti-diabetic polysaccharide from electronic databases, namely PubMed, Web of Science, ScienceDirect, and Springer, for the period 2011–2015. In total, 114 types of polysaccharides from 78 kinds of natural sources, namely plants, fungi, algae, animals, and bacteria, have shown anti-diabetic properties. In vivo and in vitro experiments have shown that administering these polysaccharides has hypoglycaemic effects and alleviates β-cell dysfunction in addtion to eliciting other anti-diabetic activities which are equally efficient to even more efficient than those of synthetic diabetic agents.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In the current unmanned aircraft systems (UASs) for sensing services, unmanned aerial vehicles (UAVs) transmit their sensory data to terrestrial mobile devices over the unlicensed spectrum. However, ...the interference from surrounding terminals is uncontrollable due to the opportunistic channel access. In this paper, we consider a cellular Internet of UAVs to guarantee the Quality-of-Service (QoS), where the sensory data can be transmitted to the mobile devices either by UAV-to-Device (U2D) communications over cellular networks, or directly through the base station (BS). Since UAVs' sensing and transmission may influence their trajectories, we study the trajectory design problem for UAVs in consideration of their sensing and transmission. This is a Markov decision problem (MDP) with a large state-action space, and thus, we utilize multi-agent deep reinforcement learning (DRL) to approximate the state-action space, and then propose a multi-UAV trajectory design algorithm to solve this problem. Simulation results show that our proposed algorithm can achieve a higher total utility than policy gradient algorithm and single-agent algorithm.
Plants benefit extensively from endophytic bacteria, which live in host plant tissues exerting no harmful effects. Bacterial endophytes promote the growth of host plants and enhance their resistance ...toward various pathogens and environmental stresses. They can also regulate the synthesis of secondary metabolites with significant medicinal properties and produce various biological effects. This review summarizes recent studies on the relationships between bacterial endophytes and medicinal plants. Endophytic bacteria have numerous applications in agriculture, medicine, and other industries: improving plant growth, promoting resistance toward both biotic and abiotic stresses, and producing metabolites with medicinal potential. Their distribution and population structure are affected by their host plant's genetic characteristics and health and by the ecology of the surrounding environment. Understanding bacterial endophytes can help us use them more effectively and apply them to medicinal plants to improve yield and quality.
A patch antenna with parasitic strips is presented for wideband circular polarization. In order to broaden the axial-ratio (AR) bandwidth of the original corner-truncated patch, four parasitic strips ...are sequentially rotated and gap-coupled around the patch. A capacitive-coupled feed with a small disc on the top of the feeding probe is utilized to obtain a wide impedance-matching bandwidth. Moreover, another disc-loaded shorting pin is placed at the center of the antenna to adjust the squint beams and improve the gains along +z-axis. Measured results show that the proposed antenna with a low profile of 0.13λ 0 obtains a global bandwidth of 24% (2.32-2.95 GHz) for |S 11 | <; -10 dB, AR <; 3 dB, and average gain of 8 dBic.
Drought has become one of the major constraints to agricultural development, particularly in areas that lack water. Studying the effects of different water stresses on the photosynthesis, growth, ...yield, water use efficiency (WUE) and irrigation water productivity (IWP) of winter wheat will provide data for the development of scientific irrigation strategies for water-saving agricultural methods. According to the size of the field water capacity, four different water stress levels were set, i.e., 30–40% (severe stress), 40–50% (moderate stress), 50–60% (mild stress) and 60–80% (well-watered) of field water capacity, controlling the amount of irrigation through an automatic irrigation system. The results showed that the seasonal changes in photosynthetic parameters, such as net photosynthetic rate (Pn), intercellular carbon concentration (Ci), stomatal conductance (Gs) and transpiration (E), significantly decreased under moderate and severe stress. As a result, the height, biomass and grain size of winter wheat decreased significantly, which led to low WUE and IWP. The Pn of the mild stress group only slightly decreased compared to that of the well-watered group, and was actually higher during the flowering and grain-filling stages, resulting in increases in dry biomass and 1000 grain weight of 2.07% and 1.95%, respectively. Higher WUE and IWP were attributed to higher yields and less water use. Thus, mild stress (60–80% field water capacity) resulted in the optimal use of water resources without a significant reduction in yield in the North China Plain (NCP). Therefore, mild stress can be considered a suitable environment for winter wheat growth in arid areas.
In this study, the water distribution and adsorption behaviors of two typical coal gasification fine slag (GFS) samples with different moisture contents were studied. Both of the samples were ...collected from entrained-flow coal gasifiers with the same coal as feedstock from Ningxia Region. The GFS sample collected from a GSP gasifier (2.5–4.0 MPa, 1400–1750°C), with lower moisture content, was named as GFS-L, and the sample collected from a Texaco gasifier (4.0–6.5 MPa, 1300–1400 °C), with higher moisture content, was GFS-H. As the water distribution and adsorption behaviors in GFS samples, largely depending on the pore structure, had not been extensively analyzed, this study was investigated by the means of nitrogen adsorption analysis, mercury intrusion porosimetry (MIP), low field nuclear magnetic resonance (LF NMR) and dynamic water vapor sorption analysis (DVS). Experimental results revealed that the surface area, pore volume and average pore diameter of GFS-L were all lower than those of GFS-H. The fractal dimension analysis results illustrated that the GFS-L sample had smoother surface but more complicated internal pore structure than the GFS-H sample. Accordingly, the moisture content in GFS-L (45.42%) was slightly lower than that in GFS-H (48.78%). Water distributed in macropores decreased significantly during dehydration process, whereas decrease of water in mesopores was not apparent. And negligible water was found in micropores. Moreover, it was found that the water adsorption behaviors in both of the GFS samples could be characterized by the monolayer adsorption and multilayer adsorption over the relative humidity (RH) range of 0–0.7. Beyond the RH range of 0.7, it was found that water adsorption in the GFS-H sample transitioned to the capillary condensation, leading to higher moisture content. This study is envisaged to provide some new insights into developing GFS dehydration technology.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
STING is an endoplasmic reticulum (ER)-associated transmembrane protein that turns on and quickly turns off downstream signaling as it translocates from the ER to vesicles. How STING signaling is ...attenuated during trafficking remains poorly understood. Here, we show that trafficking-mediated STING degradation requires ER exit and function of vacuolar ATPase complex. Late-stage STING vesicles are sorted to Rab7-positive endolysosomes for degradation. Based on analysis of existing structures, we also identified the helix amino acid 281 (aa281)–297 as a motif required for trafficking-mediated STING degradation. Immuno-electron microscopy (EM) reveals the size and clustering of STING vesicles and topology of STING on the vesicle. Importantly, blockade of trafficking-mediated STING degradation using bafilomycin A1 specifically enhanced cyclic guanosine monophosphate (GMP)-AMP (cGAMP)-mediated immune response and anti-tumor effect in mice. Together, our findings provide biochemical and imaging evidence for STING degradation by the lysosome and pinpoint trafficking-mediated STING degradation as a previously unanticipated therapeutic target for enhancing STING signaling in cancer therapy.
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•Trafficking-mediated STING degradation requires sorting of STING vesicles to lysosomes•Blockade of STING degradation enhances STING signaling and anti-tumor response•Helix aa281–297 contains a motif required for STING degradation•Trafficking-mediated STING degradation does not require downstream immune signaling
STING activation turns on and quickly turns off downstream signaling as it moves through the secretory pathway. Gonugunta et al. found that trafficking-mediated STING degradation requires ER exit and sorting of STING vesicles to lysosomes for degradation. Blockade of STING degradation enhances STING signaling and anti-tumor response.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this letter, a microstrip-fed dual-polarized stepped-impedance (SI) slot antenna element with a low profile is first proposed. The antenna is composed of two pairs of SI slots excited by two ...orthogonal stepped microstrip feedlines. The broadband characteristic is achieved by combining the fundamental and spurious resonances of the SI slot resonators, while the good cross polarization is mainly due to the introduction of the shorting pins. Secondly, based on the proposed antenna, a four-element antenna array is designed, constructed, and measured for base-station applications. Measured results demonstrate the bandwidths (return loss ) of the antenna array are 46.9% (1.55-2.5 GHz) and 38.7% (1.69-2.5 GHz) for Port 1 and Port 2, respectively. The isolation between the two ports is greater than 35 dB, whereas the cross-polarization level maintains lower than -27 dB across the entire operating band. In addition, the antenna array prototype achieves average gains of 13.5 and 13.9 dBi for horizontal polarization and vertical polarization, respectively.
STING (stimulator of interferon genes) is an important innate immune protein, but its homeostatic regulation at the resting state is unknown. Here, we identified TOLLIP as a stabilizer of STING ...through direct interaction to prevent its degradation. Tollip deficiency results in reduced STING protein in nonhematopoietic cells and tissues, and renders STING protein unstable in immune cells, leading to severely dampened STING signaling capacity. The competing degradation mechanism of resting-state STING requires IRE1α and lysosomes. TOLLIP mediates clearance of Huntington's disease-linked polyQ protein aggregates. Ectopically expressed polyQ proteins in vitro or endogenous polyQ proteins in Huntington's disease mouse striatum sequester TOLLIP away from STING, leading to reduced STING protein and dampened immune signaling. Tollip
also ameliorates STING-mediated autoimmune disease in Trex1
mice. Together, our findings reveal that resting-state STING protein level is strictly regulated by a constant tug-of-war between 'stabilizer' TOLLIP and 'degrader' IRE1α-lysosome that together maintain tissue immune homeostasis.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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