Sound source location for low-altitude aircraft based on sub-band extraction

The acoustic signal of low-altitude aircraft shows regular distribution in frequency and has obvious harmonic crest of both fundamental frequency and double frequency.Therefore, this paper presents a low complexity algorithm of acoustic location based on feature sub-band extraction for low-altitude aircraft. The algorithm firstly searches the eigenfrequency points which occupy the main energy in the sound signal. Then the cost function is constructed based on the MUSIC method by the sub-band corresponding to the eigenfrequency point. Finally, the amplitude is weighted by the maximum ratio combination principle to obtain the spectral function of array space, by which DOA estimation is realized for the spatial spectrum. Simulation results show that the algorithm is less complex than traditional wide-band DOA algorithm, and its main lobe is easier to recognize and has better spatial resolution.

Comprehensive Network Analysis and Experimental Verification of Dedu Safflower’s Influence on Ascites Hepatocarcinoma

BackgroundDedu Safflower Powder is a kind of classical prescription of Mongolian Medicine, and its main ingredients are the safflower and the Scabiosa tschiliensis. In the former Mongolian Medicine clinical practice, Dedu Safflower Powder, etc. had obvious effect on curing hepatocarcinoma so as to ease ascites. But the principle of Dedu Safflower Powder’s curing ascites hepatocarcinoma has been not clear.AimH22 mouse hepatocarcinoma ascites models are used for researching the safflower and the Scabiosa tschiliensis’s function of jointly being against hepatocarcinoma ascites, and for verifying their possible combination principle (miR-23a-DAPK1-PVT1 signal axis).MethodThrough simulating an interaction network of the safflower and the Scabiosa tschiliensis with target spots, the function target was predicted. H22 mouse hepatocarcinoma ascites models were randomly divided into a blank contrast group, a model contrast group, a safflower group, a Scabiosa tschiliensis group and a compatibility group of the safflower/the Scabiosa tschiliensis. On the 10th day, mice were killed to measure their weights and abdominal perimeters, also to collect ascites and blood for physical examinations. Kidney tissues were dissected at once and fixed in paraformaldehyde, for a real-time quantitative polymerase chain reaction (qRT-PCR) analysis.ResultIn the network, the DAPK1-PVT1 interaction showed the biggest edge betweenness, so it was predicted that DAPK1 and PVT1 were respectively presumed targets of the safflower and the Scabiosa tschiliensis. Compared with the model contrast group, the safflower group, the Scabiosa tschiliensis group and the safflower/Scabiosa tschiliensis group all had decreasing ascites volumes, body weights, abdominal perimeters. Compared with the model group, the safflower group and the safflower/Scabiosa tschiliensis group had rising DAPK1 expressions (p<0.05), while the safflower group had more obvious increasing DAPK1 (p<0.01); the Scabiosa tschiliensis group and the safflower/Scabiosa tschiliensis group had lowering PVT1 expressions (p<0.05), while the Scabiosa tschiliensis group had more obvious lowering PVT1 (p<0.01); the safflower group, the Scabiosa tschiliensis group and the safflower/Scabiosa tschiliensis group had lowering miR-23a expressions (p<0.05), while the safflower/Scabiosa tschiliensis group had more obvious lowering (p<0.01).ConclusionDAPK1 and PVT1 are respectively the presumed targets of the safflower and the Scabiosa tschiliensis. So Dedu Safflower Powder has good effects on ascites hepatocarcinoma, and that function may be partly related to regulation of miR-23a-DAPK1-PVT1 signal axis.

Design, synthesis and biological evaluation of tryptamine salicylic acid derivatives as potential antitumor agents

According to the combination principle, target compounds were designed, and compound E20 might be a promising anti-tumor agent targeting gastric cancer.

Design, synthesis, and preliminary biological evaluation of 3′,4′,5′-trimethoxy flavonoid salicylate derivatives as potential anti-tumor agents

According to the combination principle, target compounds were designed; compound10vmight be a promising multiple target anti-tumor agent candidate.

Exploring Pharmacological Mechanisms of Xuefu Zhuyu Decoction in the Treatment of Traumatic Brain Injury via a Network Pharmacology Approach

Objectives. Xuefu Zhuyu decoction (XFZYD), a traditional Chinese medicine (TCM) formula, has been demonstrated to be effective for the treatment of traumatic brain injury (TBI). However, the underlying pharmacological mechanisms remain unclear. This study aims to explore the potential action mechanisms of XFZYD in the treatment of TBI and to elucidate the combination principle of this herbal formula. Methods. A network pharmacology approach including ADME (absorption, distribution, metabolism, and excretion) evaluation, target prediction, known therapeutic targets collection, network construction, and molecule docking was used in this study. Results. A total of 119 bioactive ingredients from XFZYD were predicted to act on 47 TBI associated specific proteins which intervened in several crucial pathological processes including apoptosis, inflammation, antioxidant, and axon genesis. Almost each of the bioactive ingredients targeted more than one protein. The molecular docking simulation showed that 91 pairs of chemical components and candidate targets had strong binding efficiencies. The “Jun”, “Chen”, and “Zuo-Shi” herbs from XFZYD triggered their specific targets regulation, respectively. Conclusion. Our work successfully illuminates the “multicompounds, multitargets” therapeutic action of XFZYD in the treatment of TBI by network pharmacology with molecule docking method. The present work may provide valuable evidence for further clinical application of XFZYD as therapeutic strategy for TBI treatment.

Comparison of null models for combination drug therapy reveals Hand model as biochemically most plausible

Null models for the effect of combination therapies are widely used to evaluate synergy and antagonism of drugs. Due to the relevance of null models, their suitability is continuously discussed. Here, we contribute to the discussion by investigating the properties of five null models. Our study includes the model proposed by David J. Hand, which we refer to as Hand model. The Hand model has been introduced almost 20 years ago but hardly was used and studied. We show that the Hand model generalizes the principle of dose equivalence compared to the Loewe model and resolves the ambiguity of the Tallarida model. This provides a solution to the persisting conflict about the compatibility of two essential model properties: the sham combination principle and the principle of dose equivalence. By embedding several null models into a common framework, we shed light in their biochemical validity and provide indications that the Hand model is biochemically most plausible. We illustrate the practical implications and differences between null models by examining differences of null models on published data.

Design, synthesis and pharmacological evaluation of novel 2-chloro-3-(1H-benzo[d]imidazol-2-yl)quinoline derivatives as antitumor agents: in vitro and in vivo antitumor activity, cell cycle arrest and apoptotic response

A series of novel 2-chloro-3-(1H-benzo[d]imidazol-2-yl)quinoline derivatives were designed and synthesized as antitumor agents under the combination principle. The antitumor activity and mechanisms were then evaluated.

A conjectural variation approach to vertical integration in agricultural cooperatives

Under the assumption that agricultural cooperative is a form of vertical integration, this paper, using conjectural variations, solves the profit-maximizing problem faced by the members in the multi-plant firm model in which they are vertically integrated with the agricultural cooperative. The average principle, the marginal principle, and the linear combination principle are derived for the competitive behaviour, collusive behaviour, and Cournot behaviour, respectively. The Nash equilibrium and economic efficiency in the cooperative system are then discussed. Finally, the model is numerically solved in an illustration. The marginal principle ensures the cooperative system to remain socially optimal in the competitive market.