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An economical and green approach has been provided to turn environmental pollutants into carbon nanodots for their potential applications in both bioimaging and Fe3+ detection.

This paper studies the adaptive distributed event-triggered fault-tolerant consensus problem for a class of multi-agent systems with time delays and external disturbance. The communication faults between the agent and its neighbours are considered, and a fault-tolerant control mechanism is designed to overcome the communication faults. Moreover, a distributed event-triggered mechanism is constructed based on the distributed errors, and hence the communication burden can be reduced. Combining the Lyapunov stability theorem with the Lyapunov-Krasovskii function, it verifies that the consensus tracking errors are bounded with the guaranteed security performance, and the time delays phenomenon can also be compensated. Finally, the effectiveness and utility of the proposed control method are fully validated by two simulation examples.

The current study determined the eff ects of dietary cation-anion diff erence (DCAD) on milk performance, total apparent digestibility, and blood parameters in lactating cows subject to heat stress. Eight Chinese Holstein cows (22.04±2.38 kg of milk/d, 512±76 kg of body weight, 219±20 d in milk) at the late stage of lactation were allocated to group 1 or 2. We used a randomized complete block design with a 2x2 factorial arrangement. The experiment consisted of two periods. Each period lasted 21 days, including the first 14 days for adaptation to the diet and the following seven days for trail. During period 1, group 1 fed with DCAD at 335 mEq/kg dry matter (the basal diet=CON) and group 2 fed 507 mEq/kg dry matter (high DCAD). During period 2, group 1 diet (the basal diet = CON) was swapped group 2 diet (high DCAD). The high DCAD had no significant eff ects on the respiratory frequency, rectal temperature, blood pH value, the acid-base balance, milk yield, milk composition, and feed intake (P>0.05). However, the high DCAD was associated with lower somatic cell count (SCC) in milk (P=0.04) and lower immune cell counts in blood, which was conducive to the improvement of milk quality. The apparent digestibility of dry matter, organic matter, energy, neutral detergent fiber, and ethyl extract was greater in the high DCAD group (P

Analysis of a single-span bridge with rubber bearing as the isolation system is performed under earthquakes. The conventional bridge seismic design requires the whole structure to be perfectly connected to avoid interrupting the transfer of earthquake energy from the ground through the bridge. A bridge with this typical design requires a high-cost construction due to the need for a huge section of the bridge to resist the earthquake force demand. Thus, many bridges in Taiwan are designed with a rubber bearing only put in between the column and girder without an anchor system. Thus, the bridge movement by rubber displacement is permissible, but the sliding displacement must be accommodated to limit the movement. The sliding displacement is the method to exploit the friction force provided by the sliding on the top and bottom interface of the rubber with the girder and column to dissipate the earthquake input energy transmitted to the structure. By involving the role of surface friction, the shear force transmitted to the structure can be reduced and the bridge performance optimized. General Functional Bearing Model (GFBM) analysis is a rubber bearing analysis which unmerges the function of friction and restoring force. In contrast with the conventional method, the rubber bearing designed with GFBM analysis may reduce the bridge stiffness and deck acceleration, and it is more convenient because only sliding displacement needs to be controlled. This research proposed GFBM analysis to simulate the rubber bearing that is reflected in the real conditions of bridges in Taiwan.

The amalgamation of the Yangtze and the Cathaysia Block in Neoproterozoic time led to the formation of the South China Block (SCB) and generated the Jiangnan Orogen with the occurrences of juvenile magmatic rocks. After this orogeny, a typical collisional orogen formed during the early Paleozoic period in Southeast Asia which is mainly distributed in the Wuyi-Nanling-Yunkai area in the SCB. However, the transitional time from syn-collisional compression to post-collisional extension is debatable. Here, we present new data on zircon U-Pb zircon ages, Lu-Hf isotopes, and geochemistry for the Guzhang and Shadi granites from the Nanling area, South China. Both plutons have similar zircon 238U/206Pb ages of ca. 430 Ma. Petrographic and geochemical characteristics (e.g., FeOt/(FeOt+MgO) = 0.82–0.95) indicate that both granites are peraluminous A-type, with high Ga/Al ratios (2.43–2.91) as well as high concentrations of Zr, Nb, Ce, Y (sum values from 327 to 527 ppm), and formation temperature (820°C–845°C). Shadi granite exhibit high positive εHf(t) values (clustering within 0 to +6) while Guzhang granite show relatively lower εHf(t) values (−8.7 to −2.9). Their mildly negative to positive zircon εHf(t) values are higher than that of many coeval granites and can be derived from anhydrous melting of tonalitic genesis in the middle crustal depth, with the Shadi pluton having more orthometamorphite in the source. The ages and Hf isotopic compositions of inherited zircons (εHf(t = 960 Ma) = 9.2, εHf(t = 950 Ma) = 7.3) suggest that the Neoproterozoic juvenile magmatic rocks in the Jiangnan Orogen were a significant source for these granites. We interpret these A-type granites derived at the post-collisional stage. Their occurrence indicates that the geological setting of this Paleozoic orogen shifted from compression to extension no later than 430 Ma.

A new indole diketopiperazine alkaloid, named penilline D (1), together with five known indole alkaloid analogues (2-5, 11), two meroterpenoids (6 and 12), and four butenolide derivatives (7-10), were isolated from the Antarctic fungus Penicillium sp. SCSIO 05705. Extensive spectroscopic analysis and electronic circular dichroism (ECD) calculation were used to elucidate the structure of penilline D (1), including its absolute configuration. All isolated compounds (1-12) were evaluated for their cytotoxic, antibacterial and enzyme inhibitory activities against acetylcholinesterase (AChE) and pancreatic lipase (PL). Among them, compound 5 exhibited moderate in vitro cytotoxic activity against the 143B cell line with IC50 value of 12.64 ± 0.78 μM. Compound 6 showed strong inhibitory activity against AChE with IC50 value of 0.36 nM (IC50 18.7 nM for Tacrine), while compounds 6 and 11 showed weak PL enzyme inhibitory activity. Furthermore, an in silico molecular docking study was also performed between 6 and AChE.

Oesophageal adenocarcinoma (EAC) is a highly lethal cancer associated with a rapidly rising incidence and a poor prognosis. Alantolactone, a sesquiterpene lactone isolated from inula helenium, has anti-inflammatory, antimicrobial, neuroprotective activities, and anticancer properties.In the present study, the anticancer effects of alantolactone on the human EAC cells were investigated in vitro and in vivo.After treated with alantolactone, the cell viability of KYAE-1, KYAE-2, OE19, and OE33 cells reduced significantly compared with that of the control cells. Alantolactone induced apoptosis of the EAC cell lines by inhibiting the protein expression levels of nuclear factor erythroid2-related factor 2 (Nrf2). Furthermore, the apoptosis-inducing effect of alantolactone was enhanced by Nrf2 knockdown while reduced by overexpression of Nrf2. Antioxidant α-tocopherol and glutathione can protect EAC cell lines against alantolactone. A xenograft nude mice model showed that alantolactone can inhibit EAC growth in vivo.Alantolactone inhibits oesophageal adenocarcinoma cells through Nrf2-mediated reactive oxygen species (ROS) increment. Alantolactone maybe a potential therapeutical candidate for treating EAC.

Atherosclerosis is a chronic arterial wall illness that forms atherosclerotic plaques within the arteries. Plaque formation and endothelial dysfunction are atherosclerosis' characteristics. It is believed that the occurrence and development of atherosclerosis mainly include endothelial cell damage, lipoprotein deposition, inflammation and fibrous cap formation, but its molecular mechanism has not been elucidated. Therefore, protecting the vascular endothelium from damage is one of the key factors against atherosclerosis. The factors and processes involved in vascular endothelial injury are complex. Finding out the key factors and mechanisms of atherosclerosis caused by vascular endothelial injury is an important target for reversing and preventing atherosclerosis. Changes in cell adhesion are the early characteristics of EndMT, and cell adhesion is related to vascular endothelial injury and atherosclerosis. Recent researches have exhibited that endothelial-mesenchymal transition (EndMT) can urge atherosclerosis' progress, and it is expected that inhibition of EndMT will be an object for anti-atherosclerosis. We speculate whether inhibition of EndMT can become an effective target for reversing atherosclerosis by improving cell adhesion changes and vascular endothelial injury. Studies have shown that H2S has a strong cardiovascular protective effect. As H2S has anti- inflammatory, anti-oxidant, inhibiting foam cell formation, regulating ion channels and enhancing cell adhesion and endothelial functions, the current research on H2S in cardiovascular aspects is increasing, but anti-atherosclerosis's molecular mechanism and the function of H2S in EndMT have not been explicit. In order to explore the mechanism of H2S against atherosclerosis, to find an effective target to reverse atherosclerosis, we sum up the progress of EndMT promoting atherosclerosis, and Hydrogen sulfide's potential anti- EndMT effect is discussed in this review.

As an important part and the core link of a terrestrial ecosystem, terrestrial vegetation is the main means for human to regulate climate and mitigate the increase in atmospheric CO2 concentration. The Yangtze River Delta (YRD) region is an urban agglomeration with the strongest comprehensive strength among developing countries (China). In the context of global climate change, a rapid, comprehensive, and detailed understanding of the spatio-temporal characteristics and variation tendency of the net ecosystem productivity (NEP) of vegetation and its response to climate during the rapid development of the YRD region is important for protecting ecological land, strengthening land management, and optimizing urban planning. The monthly mean temperature and rainfall data from 63 meteorological stations, the MODIS net primary productivity product, and a land cover product in the YRD region were used to estimate the NEP from 2000 to 2019 based on the soil respiration model, and the correlation between NEP and meteorological factors (such as temperature and rainfall) was analyzed. The results showed that: (1) From 2000 to 2019, the carbon sink area was much larger than the carbon source area in terrestrial vegetation in the Yangtze River Delta, the mean NEP of the vegetation ecosystem in the past 20 years was 253.2 g C·m−2·a−1, and the spatial distribution presented a trend that was higher in the south and lower in the north, higher in the east and lower in the west, and that gradually increased from northwest to southeast; moreover, the NEP of mountain areas was generally higher than that of river courses and urban surroundings. The interannual fluctuation of NEP was small, but presented a slightly increasing trend, and the interannual variation of NEP was significantly correlated with the maximum NEP in this region. (2) The carbon sink capacity of different vegetation cover types was (from strong to weak): forestlands > grasslands > wetlands ≈ croplands. (3) The area with the NEP change rate (θslope) > 0 accounted for 69.0%; however, there was certain spatial difference, the proportions of the areas with θslope < 0 were (from large to small) 14.50% (Zhejiang Province, China), 9.10% (Anhui Province, China), 6.65% (Jiangsu Province, China), and 0.79% (Shanghai, China). In terms of the individual changes of these provinces and municipalities, Shanghai > Zhejiang Province > Jiangsu Province ≈ Anhui Province. (4) There was a correlation between NEP and the annual mean temperature and annual precipitation in some regions.

A new furanone analog, (

A distributed event-triggered consensus control protocol is proposed for a class of nonlinear multi-agent systems with switching topologies. The nonlinear dynamics and switching topologies are considered simultaneously to adapt to some actual scenarios. To economize the communication resources, a distributed event-triggered mechanism is established to decrease the consumption of communication resources. The new event-triggered mechanism is constructed by the information of distributed errors, which can fully utilize communication relationships among agents to control the timing of events. A class of negative exponential functions is added to the event-triggered condition as the event-triggered mechanism is applied for the presented multi-agent systems. The design of event-triggered condition can reduce the occurring frequency of events when the adjusting time of control scheme begins at an initial small amount period of time. Finally, the simulation results are provided, which verify the feasibility and effectiveness of the designed event-triggered consensus control strategy for the presented multi-agent systems with switching topologies.

Atherosclerosis (AS) is a chronic inflammatory disease accompanied by complex pathological changes, such as endothelial dysfunction, foam cell formation, and vascular smooth muscle cell proliferation. Many approaches, including regulating AS-related gene expression in the transcriptional or post-transcriptional level, contribute to alleviating AS development. The DNA methylation is a crucial epigenetic modification in regulating cell function by silencing the relative gene expression. The microRNA (miRNA) is a type of noncoding RNA that plays an important role in gene post-transcriptional regulation and disease development. The DNA methylation and the miRNA are important epigenetic factors in AS. However, recent studies have found a mutual regulation between these two factors in AS development. In this study, recent insights into the roles of miRNA and DNA methylation and their interaction in the AS progression are reviewed.

Euroticins C–E (1–3), three pairs of salicylaldehyde derivative enantiomers, were isolated from a marine-derived fungus Eurotium sp. SCSIO F452. They represent two types of salicylaldehyde derivatives bearing unprecedented highly constructed 6/6/6/6 tetracyclic structures. Their structures were established by comprehensive spectroscopic analyses, X-ray diffraction, and electronic circular dichroism calculations. Compounds (+)-1 and (−)-1 showed significant antioxidative activity and moderate cytotoxic activity.

A new dual-decontamination strategy has been employed to synthesize graphitic carbon nanosheets (GCNs) from Reactive Red 2, a common chemical pollutant in textile wastewater, for efficient tetracycline (TC) degradation via nonradical oxidation processes. Detailed physical characterization indicates that the GCN possesses a layered and flat structure, high microporosity, and microscopic configuration of graphene-like nanosheets with abundant surface O-, N- and S-containing functional groups (including graphitic N and carbonyl groups). From the kinetic model, quenching experiments and mechanism studies, only 1O2 is detected in the GCN/PMS system, without SO4˙−, HO˙ or O2˙−. 1O2 contributed to only 17.8% of overall TC degradation. Surface-confined electron transfer appears to be the major oxidation pathway (82.2%) for TC degradation. Furthermore, full-scale biological assays verify that the biotoxicity of the TC degradation products is significantly reduced in comparison with that of the precursor. This work provides a new insight toward the conversion from a chemical pollutant into a metal-free carbon catalyst for wastewater treatment.

Dendritic cells (DC) are the most important antigen-presenting cells, which guide T cell activation and function, and dysregulated DC function might be one of the crucial causes of inflammatory bowel disease (IBD). It has been well-known that microbiota and their metabolites play an essential role in regulating the biology and function of DC, thus contributing to the pathogenesis of IBD. However, the underlying mechanisms remain largely unknown. Amphiregulin (AREG), a molecule of the epidermal growth factor (EGF) family, is primarily described as an epithelial cell-derived cytokine and recognized as a critical regulator of cell proliferation and tissue repair. Here, we found that DC expression of AREG depended on butyrate (a microbiota-derived short chained fatty acid), which required the interaction between butyrate and G-protein-coupled receptor 43 (GPR43). Furthermore, we found that butyrate-GPR43 interaction failed to induce AREG expression in DC deficient in B lymphocyte induced maturation protein 1 (Blimp-1). Notably, DC-derived AREG was indispensable for the protection against experimental colitis in mice. Additionally, AREG expression was significantly decreased in DC from IBD patients. Our data provide novel evidences to interpret how AREG expression is regulated in DC, and shed new light on the mechanisms whereby microbiota regulate DC function.

The beef cattle industry in China has advanced remarkably since its reform and opening up; consequently, China has become the world’s third-largest beef cattle producer. China is also one of the countries with the most substantial research input and output in the field of beef cattle feed and nutrition. The progress and innovation by China in the research field of beef cattle feed and nutrition have undoubtedly promoted the development of the domestic beef cattle industry. This review summarizes recent advances in feed resource development, nutrient requirements, and nutritional regulation of beef cattle in China. Limitations in current research and perspectives on future work are also discussed.

DC-DC converters work as one of the crucial components in DC microgrid intergraded power systems. In this brief, the robust output voltage regulation problem of DC-DC boost converter system is addressed by using a continuous nonsingular terminal sliding mode control (CTSMC) technique based on finite-time disturbance observer. By integrating the disturbance estimations into the controller design, an improved sliding mode control (SMC) approach is developed to achieve better voltage tracking performance. The proposed control method admits the properties of fast transient responses, strong suppression ability against time-varying disturbances and small steady state oscillations of output voltage. Experimental results in the presence of both load variations and supplied voltage fluctuations are provided to validate the effectiveness of the proposed algorithm.

DC-DC buck converters are widely used in industrial applications. Practically, there are parametric uncertainties, external disturbances and nonlinear unmodeled dynamics affecting the control performance of the DC-DC buck converters. Worse still, the current sensor may fail to work normally in practice. Taking the factors aforementioned into account, this paper proposes a universal finite-time observer (UFTO) based second-order sliding mode controller with only output voltage measurement in a simple structure for buck converters subject to mismatched disturbances. Firstly, a universal finite-time observer is designed to give the estimations of unmeasurable states including the current inductor and lumped disturbances. Secondly, introducing the estimations, a second-order sliding mode controller is proposed and a rigorous stability of the whole system is presented. Under the proposed finite-time controller, the system obtains a better convergence property and a better disturbance rejection ability comparing with the asymptotic control method. Moreover, the controller has a simple structure, providing convenience for engineers. As a by-product, only voltage sensor is needed, which reduces the cost and improves the fault tolerant ability for the system. Simulation and experimental results are investigated to validate the effectiveness of the proposed control approach.