A New Anthracene Derivative from Marine Streptomyces sp. W007 Exhibiting Highly and Selectively Cytotoxic Activities

A new anthracene derivative, 3-hydroxy-1-keto-3-methyl-8-methoxy-1,2,3, 4-tetrahydro-benz[α]anthracene, was isolated from the marine strain Streptomyces sp. W007, and its structure was established by spectroscopic analysis including mass spectra, 1D- and 2D-NMR (1H–1H COSY, HMBC, HSQC and NOESY) experiments. 3-hydroxy-1-keto-3-methyl-8-methoxy-1,2,3,4-tetrahydro-benz[α]anthracene showed cytotoxicity against human lung adenocarcinoma cell line A549

Three-Dimensional Stochastic Distribution Characteristics of Void Fraction in Longwall Mining-Disturbed Overburden of Inclined Coal Seam

AbstractFractures in the overburden induced by mining disturbances provide a channel for fluid flow between the surface and the underground. Mining-induced strata movement and fracture distribution are influenced by the gravity and dip angles of rock seams. In this paper, a new three-dimensional theoretical distribution model for void fraction in each partition of overlying rock strata disturbed by inclined coal seam mining was constructed. Based on the theoretical determination model, the three-dimensional random distribution characteristics for void fraction were obtained by combining the random distribution law of void fraction obtained by similar physical simulation experiments and image processing techniques. Theoretical deterministic models, stochastic theoretical models, and similar physical simulations all show that void fraction distribution in the tendency direction of the coal seam shows a bimodal asymmetric distribution with high and low peaks and a symmetric distribution in the strike direction. The void fraction of the overburden in the central part of the mining area is smaller than that of the surrounding area. The results of the theoretically determined model and stochastic model of the void fraction for the strata with different mining lengths and different coal seam inclinations were compared with the results of similar simulation experiments, respectively. The results are in agreement, further verifying the practicality of the model

Vibration wave downhole communication technique

To overcome the disadvantages of traditional downhole communication methods, a vibration wave downhole communication technique is proposed, and a vibration wave downhole communication system is developed. This technique has been verified by field test and is applied to separated layer water injection. It is shown by theoretical and test research that transmission of the vibration wave through tubing and casing appears as the alternate distribution of pass-band and stop-band. According to that, a multi-baseband transmission strategy is formulated. The on-off keying modulation and Manchester encoding scheme are used to load the control information into the vibration wave. A generation system of vibration signals is developed to realize the controllable conversion from electric energy into vibration wave energy. A receiving and decoding system of vibration waves, which uses a micro-vibration acceleration sensor as the signal pickup element, is developed too. A test system for vibration wave downhole remote transmission is designed and applied to field test. The feasibility of the technique and the accuracy and reliability of communication system are verified and the attenuation characteristics of casing vibration wave signals are obtained. This technique has been applied to separated layer water injection successfully with wide application prospect in wellbore control field. Key words: vibration wave, downhole communication, on-off-keying modulation, Manchester encoding, magne-tostrictive material, micro-vibration acceleration senso

Combustion mechanism and control approaches of underground coal fires: a review

Abstract With the large-scale mining of coal resources, the huge economic losses and environmental problems caused by underground coal fires have become increasingly prominent, and the research on the status quo and response strategies of underground coal fires is of great significance to accelerate the green prevention and control of coal fires, energy conservation and emission reduction. In this paper, we summarized and sorted out the research status of underground coal fires, focused on the theoretical and technical issues such as underground coal fire combustion mechanism, multiphysics coupling effect of coal fire combustion, fire prevention and extinguishing technology for underground coal fires, and beneficial utilization technology, and described the latest research progress of the prevention and control for underground coal fire hazards. Finally, the key research problems in the field of underground coal fire hazards prevention and control were proposed in the direction of the basic theory, technology research, comprehensive management and utilization, with a view to providing ideas and solutions for the management of underground coal fires

An Optimization Method for Local Consumption of Photovoltaic Power in a Facility Agriculture Micro Energy Network

In order to solve the problem of optimal dispatching of photovoltaic power for local consumption to the greatest degree in a photovoltaic greenhouse, this paper proposes a multiform energy optimal dispatching model and a solution algorithm. First, an input-output power model is established for energy storages which are reservoir, biogas digester, and block wall with phase-change thermal storage. Based on it, multiform energy storages play a bridging role of energy transfer in optimal energy dispatching. Subsequently, an optimal energy dispatching model is proposed with the objective of minimizing the sum of the squares of the difference between the loads and the photovoltaic generation in dispatching periods. Control variables are working state quantities of the time-shiftable loads and input-output state quantities of energy storages in dispatching periods. Finally, a genetic algorithm with matrix binary coding is used to solve the energy optimal dispatching model. Simulation results of a practical photovoltaic greenhouse facility agricultural micro energy network system in three typical weather conditions showed that the method could fully utilize the energy transfer function of the multiform energy storage and the time-shiftable characteristics of the agricultural load to achieve the maximum effect of increasing the local consumption of the photovoltaic power

Case Library Construction Technology of Energy Loss in Distribution Networks Considering Regional Differentiation Theory

The grid structures, load levels, and running states of distribution networks in different supply regions are known as the influencing factors of energy loss. In this paper, the case library of energy loss is constructed to differentiate the crucial factors of energy loss in the different supply regions. First of all, the characteristic state values are selected as the representation of the cases based on the analysis of energy loss under various voltage classes and in different types of regions. Then, the methods of Grey Relational Analysis and the K-Nearest Neighbor are utilized to implement the critical technologies of case library construction, including case representation, processing, analysis, and retrieval. Moreover, the analysis software of the case library is designed based on the case library construction technology. Some case studies show that there are many differences and similarities concerning the factors that influence the energy loss in different types of regions. In addition, the most relevant sample case can be retrieved from the case library. Compared with the traditional techniques, constructing a case library provides a new way to find out the characteristics of energy loss in different supply regions and constitutes differentiated loss-reducing programs

Platelet Membrane Nanocarriers Cascade Targeting Delivery System to Improve Myocardial Remodeling Post Myocardial Ischemia–Reperfusion Injury

Abstract Although treatments for myocardial infarction have advanced significantly, the global mortality due to ischemia and subsequent reperfusion injury remains high. Here, a platelet (PLT) membrane nanocarrier (PL720) that encapsulates L‐arginine and FTY720 to facilitate the cascade‐targeted delivery of these substances to the myocardial injury site and enable the controlled release of L‐arginine and FTY720 is developed. Such an innovative approach shows enhanced cardioprotection through multiple target strategies involved in ischemia–reperfusion injury and late reperfusion inflammation. During the ischemia–reperfusion phase, PL720 targets and accumulates in damaged coronary arteries. PL720 rapidly releases L‐arginine, stimulating endothelial cells to produce NO, thereby dilating blood vessels and promoting blood flow recovery, while FTY720's sustained release exerts anti‐apoptotic effects. During the late reperfusion inflammatory phase, PL720 is captured by circulating inflammatory monocytes and transported into a deeper ischemic myocardial lesion. PL720 promotes macrophage polarization and accelerates the inflammatory repair. Furthermore, the issue of bradycardia associated with the clinical use of FTY720 is innovatively relieved. Therefore, PL720 is a vascular injury and inflammation dual targeting strategy, exhibiting significant potential for multi‐targeted therapy and clinical translation for cardiac injury