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A mild and efficient strategy for the synthesis of tricyclic 1,2,4-oxadiazolines-fused tetrahydro-isoquinolines derivatives via [3 + 2] cycloaddition reaction is reported. The reactions provided the functionalized tricyclic 1,2,4-oxadiazolines in high yields (up to 96%). This protocol is simple and easy to handle. Moreover, a gram-scale experiment further highlights the synthetic utility. The chemical structure of the product was determined by X-ray single-crystal structure analysis. A possible mechanism for this transformation is proposed to explain the reaction process.

Enterprises’ green technology innovation is critical to achieving the “win-win” of enterprise competitiveness and environmental protection. The impact of environmental regulation on green technology innovation by enterprises has been widely considered, but the conclusion has not yet been determined, and needs to be studied in detail. To this end, we studied the impact of pollution charge policy on different types of green technology innovation by industrial enterprises in China. We found that (1) the impact of pollution charges on most types of green technology innovation by enterprises has increased significantly over time; (2) the pollution charge policy has a certain inhibition effect on the end-of-pipe technology innovation, but can promote the process improvement of reducing industrial wastewater emissions; (3) there is a U-shaped relationship between the pollution charges and some green technological innovation (e.g., emission intensity of SO2, industrial wastewater emission intensity, and industrial wastewater removal intensity), which is dynamically adjusted over time; and (4) the larger the enterprise’s solid assets, the faster the asset depreciation will inhibit the enterprise from adopting the green process innovation strategy.

Naringenin (NRG) is a natural flavonoid compound abundantly present in citrus fruits and has the potential to treat respiratory disorders. However, the clinical therapeutic effect of NRG is limited by its low bioavailability due to poor solubility. To enhance the solubility, naringenin nanosuspensions (NRG-NSps) were prepared by applying tocopherol polyethylene glycol succinate (TPGS) as the nanocarrier via the media-milling method. The particle size, morphology, and drug-loading content of NRG-NSps were examined, and the stability was evaluated by detecting particle size changes in different physiological media. NRG-NSps exhibited a flaky appearance with a mean diameter of 216.9 nm, and the drug-loading content was 66.7%. NRG-NSps exhibited good storage stability and media stability. NRG-NSps presented a sustainable release profile, and the cumulative drug-release rate approached approximately 95% within 7 d. NRG-NSps improved the antitussive effect significantly compared with the original NRG, the cough frequency was decreased from 22 to 15 times, and the cough incubation period was prolonged from 85.3 to 121.6 s. Besides, NRG-NSps also enhanced expectorant effects significantly, and phenol red secretion was increased from 1.02 to 1.45 μg/mL. These results indicate that NRG-NSps could enhance the bioavailability of NRG significantly and possess a potential clinical application.

In the operation process of a power battery pack, the inconsistency among lithium-ion cells may seriously restrict the pack’s capacity, power capability and lifetime, which may bring hidden danger to the use of electric vehicles. Equalization management systems (EMSs) are crucial to alleviate such inter-cell inconsistency, whose performance such as accuracy and stability, mainly depends on the setting of equalization control strategies. This paper proposes an equalization strategy aimed at throughput maximization of series battery in the whole life cycle based on Model Prediction Control (MPC). In this paper, a Mean-plus-difference model (M+D) model is selected as the series battery model and the parameters are identified by Recursive Least Squares (RLS). Based on the model predictive control theory, the control model of series battery pack is established and the objective function of maximizing the throughput in the whole life cycle is derived. At the end of the paper, the simulation results show that the proposed equalization strategy can achieve greater life cycle throughput compared with the traditional SOC equalization strategy, which verifies the guiding significance of the equilibrium strategy proposed in this paper.

Esophageal squamous cell carcinoma (ESCC), which is characterized by invasiveness and poor prognosis, is the sixth most common leading cause of cancer-related death worldwide. Despite advances in multimodality therapy, ESCC mortality remains high, and an understanding of the molecular changes that lead to ESCC development and progression remains limited. In the present study, Integrin Binding Sialoprotein (IBSP) upregulation was found in 182 of 269 (67.7%) primary ESCC cells at the mRNA level by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, IHC staining further demonstrated that IBSP was upregulated in ESCC patients and IBSP protein upregulation was significantly related to the lymph node metastasis (P = 0.017), clinicopathologic stage (P = 0.001) and poor disease survival (P = 0.002). Moreover, functional studies illustrated that the IBSP gene can promote the proliferation and metastasis of ESCC cells. Furthermore, IBSP was found to regulate epithelial-mesenchymal transition (EMT), which promotes tumor cell metastasis. In conclusion, our study suggests that IBSP may be a valuable prognostic marker for ESCC patients.

This paper studies the evolutionary characteristics of international trade of potassium salts. We construct a weighted and directed complex network model of potassium salt trade, analyze the scale and activity, trade relations, trade flow distribution and the importance of trading countries using UN Comtrade2000-2016 data. Results show that potassium salt trade is more dynamic, resource allocation is more convenient. Some countries have formed trade groups. The relationship between small and major countries is growing. The resource flows of countries with large degrees are conducive to balancing resource’s distribution. Besides Canada is a leading trade country, and the US, the Russian Federation, China and Brazil are trade-led countries. China, the Netherlands, the US, France and India are important hubs. Finally, using Porter's national competitive advantage theory, it proposes countermeasures for forming the international competitive advantage of potassium salt enterprises in different countries.

Despite the high potential impact of aqueous battery systems, fundamental characteristics such as cost, safety, and stability make them less feasible for large-scale energy storage systems. One of the main barriers encountered in the commercialization of aqueous batteries is the development of large-scale electrodes with high reversibility, high rate capability, and extended cycle stability at low operational and maintenance costs. To overcome some of these issues, the current research work is focused on a new class of material based on phenethylammonium bismuth iodide on fluorine doped SnO2-precoated glass substrate via aerosol-assisted chemical vapor deposition, a technology that is industrially competitive. The anode materials were electrochemically investigated in Zn2+ aqueous electrolytes as a proof of concept, which presented a specific capacity of 220 mAh g−1 at 0.4 A g−1 with excellent stability after 50 scans and capacity retention of almost 100%.

A dual D-type photonic crystal fiber (PCF) was proposed in this work to measure the refractive index and temperature of seawater. Two golden layers were designed to be coated on the two polished planes in the dual D-type PCF. Two confinement loss peaks in the transmission spectrum appeared due to the surface plasmon resonances which were inspired on the two golden layers. In order to achieve two-parameter sensing, one of the two polished planes was further coated with a polydimethylsiloxane (PDMS) layer which was temperature-sensitive. Seawater was assumed to be coated on the outer surface of the PCF. Numerical results by using the finite element method showed that the measurement sensitivity of the refractive index of seawater reached 1371 and 1228 nm/RIU, while the measurement sensitivity of temperature reached −0.3 and −1.06 nm/ °C, respectively. Finally, we obtained the transfer matrix expression which could be used to measure the refractive index and temperature of seawater simultaneously. The designed dual D-type PCF, which is simple in structure, highly sensitive and two-parameter measuring, could be a promising candidate for the monitoring of seawater.

Graphene’s many excellent properties have cemented it as an essential research topic in materials science and beyond. It is widely used in photoelectric materials, sensors, battery electrode materials, composites, and so on. Graphene has attracted particular attention in the field of tribology. However, graphene agglomerates easily, limiting its performance when used directly. Therefore, considerable research has focused on methods of modifying the surface of graphene to improve its tribological performance, by improving the dispersion stability, friction reduction, wear resistance, or a combination of these. This paper focuses on the research progress of surface modification of graphene-based materials for tribological applications. According to the reaction principles, surface modification methods can be divided into covalent surface modification, noncovalent surface modification, and surface modification by nanoparticles doping. Herein, the typical reaction processes of these modification methods and the anti-wear mechanism of modified graphene-based materials are introduced, and current research on the surface modification of graphene used in tribology is discussed.

(1) Background: The widespread use of insecticides has cause extensive resistance in German cockroach (Blattella germanica) populations globally. Biological control has the potential to mitigate insecticide resistance, and Metarhizium anisopliae (Meschn.) Sorokin, an entomopathogenic fungus, alone and in combination with various insecticides, has shown good effects against cockroaches. (2) Methods: This experiment compared the cumulative mortality after infecting B. germanica with M. anisopliae conidia by two routes, per os and topical application. To probe the mechanisms that underlie the synergism between M. anisopliae and hydramethylnon, we conducted dose–response assays with cockroaches fed combinations of M. anisopliae and hydramethylnon and characterized the gut microbiomes of the treated cockroaches. (3) Results: The study showed that the mortality with per os infection was lower than that with topical application. In addition, the combination of M. anisopliae and hydramethylnon had a synergistic effect in 16 treatments. The gut microbiome was also altered by hydramethylnon treatment. The abundance of Parabacteroides and Enterococcus declined with the hydramethylnon and combination treatments, which are known to have anti-inflammatory and antifungal activities. The abundance of Alistipes, which is a fungal cell wall component, significantly increased in these treatments. (4) Conclusions: Therefore, we speculate that the major mechanism underlying this synergism is hydramethylnon promoting the survival of M. anisopliae in the harsh gut environment and enhancing its virulence for German cockroaches by altering the gut microbiome. This may provide a method for the fight against B. germanica and lay the foundation for the development of new baits.

Research on vegetation variation is an important aspect of global warming studies. The quantification of the relationship between vegetation change and climate change has become a central topic and challenge in current global change studies. The source region of the Yellow River (SRYR) is an appropriate area to study global change because of its unique natural conditions and vulnerable terrestrial ecosystem. Therefore, we chose the SRYR for a case study to determine the driving forces behind vegetation variation under global warming. Using the Normalized Difference Vegetation Index (NDVI) and climate data, we investigated the NDVI variation in the growing season in the region from 1998 to 2016 and its response to climate change based on trend analysis, the Mann–Kendall trend test and partial correlation analysis. Finally, an NDVI–climate mathematical model was built to predict the NDVI trends from 2020 to 2038. The results indicated the following: (1) over the past 19 years, the NDVI showed an increasing trend, with a growth rate of 0.00204/a. There was an upward trend in NDVI over 71.40% of the region. (2) Both the precipitation and temperature in the growing season showed upward trends over the last 19 years. NDVI was positively correlated with precipitation and temperature. The areas with significant relationships with precipitation covered 31.01% of the region, while those with significant relationships with temperature covered 56.40%. The sensitivity of the NDVI to temperature was higher than that to precipitation. Over half (56.58%) of the areas were found to exhibit negative impacts of human activities on the NDVI. (3) According to the simulation, the NDVI will increase slightly over the next 19 years, with a linear tendency of 0.00096/a. From the perspective of spatiotemporal changes, we combined the past and future variations in vegetation, which could adequately reflect the long-term vegetation trends. The results provide a theoretical basis and reference for the sustainable development of the natural environment and a response to vegetation change under the background of climate change in the study area.

The decomposition processes of accumulated cyanobacteria can release large amounts of organic carbon and affect the carbon cycling in shallow eutrophic lakes. However, the migration and transformation mechanisms of dissolved carbon (DC) require further study and discussion. In this study, a 73-day laboratory microcosm experiment using suction samplers (Rhizon and syringe) was conducted to understand the migration and transformation of DC during the cyanobacteria decomposition. The decomposition of cyanobacteria biomass caused anoxic and reduction conditions, and changed the acid-base environment in the water column. During the early incubation (days 0–18), a large amount of cyanobacteria-derived particulate organic matter (POM) was decomposed into dissolved organic carbon (DOC) in the overlying water, reaching the highest peak value of 1.82 g L−1 in the treatment added the high cyanobacteria biomass (470 g). After 18 days of incubation, the mineralization of increased DOC to dissolved inorganic carbon (DIC) maintained a high DIC level of overlying water in treatments added cyanobacteria biomass. The treatment added the medium cyanobacteria biomass (235 g) presented the lower DOC/total dissolved carbon ratio than the high cyanobacteria biomass associated with the lower mineralization from DOC to DIC. Due to the concentration differences of DIC at water-sediment interface, the main migration of DIC from pore water to overlying water occurred in the treatment without added cyanobacteria biomass. However, the treatments added the cyanobacteria biomass presented the obvious diffusion of DOC and the low migration of DIC at the water-sediment interface. The diffusive fluxes of DOC at the water-sediment interface increased with the cyanobacteria biomass added, reaching the maximum value of 411.01 mg/(m2·d) in the treatment added the high cyanobacteria biomass. In the overlying water, the group added the sediment and medium cyanobacteria biomass presented a faster degradation of cyanobacteria-derived POM to DOC and a higher mineralization level of DOC to DIC than added the medium cyanobacteria biomass without sediment. Therefore, during accumulated cyanobacteria decomposition, the biomass of accumulated cyanobacteria and sediment property can influence the migration and transformation of DC, playing an important role in carbon cycling in shallow eutrophic lakes.