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Main observation and conclusion: Sarcaglarols A—D (1—4), two pairs of lindenane−monoterpene heterodimers fused by a 1,2‐dioxane moiety, were discovered and isolated from the leaves of Sarcandra glabra guided by MS/MS molecular networking‐based strategy. Their planar structures, absolute configurations of basic skeleton and flexible polyhydric side chain were established by analysis of HRESIMS, NMR spectroscopic data, ECD spectrum, and the X‐ray diffraction study of isopropylidene derivatives. An intermolecular [2+2+2] cycloaddition may play a key role in the biosynthesis pathway of the 1,2‐dioxane moiety fused lindenane−monoterpene heterodimer skeleton, which can be recognized as the biogenetic precursors of our previous reported lindenane−normonoterpene conjugates. In addition, compounds 1, 3 and 4 exhibited moderate inhibitory effects of lipid accumulation in free fatty acid‐exposed L02 cells. [ABSTRACT FROM AUTHOR]

Disputes over Ovid's genuine attitudes towards Roman emperor Octavian have never ceased among Western scholars of classics. Never a motivated dissident, Ovid was unfortunately an adherent to the idea of artistic autonomy, which, against the backdrop of a unified Augustan cultural order, was interpreted by the imperial family as a political stance. In order to return to Rome or suffer less severely, the banished poet would have to appease the emperor with servile penitence, but Ovid was frequently impelled by his obstinacy as an artist and indignation at his unmerited torments to overlook his real-life needs and give his works an ironic twist. While in some poems, his venom of criticism is ingeniously dissimulated beyond easy detection, his defiance is alarmingly obvious in others. Although Octavian, Livia, and Tiberius usually appear as gods in Tristia and Ex Ponto, they are revealed, through various means of artistry, to be no more than ruthless rulers on earth whose self-imposed apotheosis is constantly ridiculed. [ABSTRACT FROM AUTHOR]

The effects of the warm forming temperature on the axial-pushed incremental rolling process were investigated through finite element analysis and experimental studies. Firstly, the principle of warm axial-pushed incremental rolling process of spline shaft was introduced. Next, the material properties of 42CrMo steel at different forming temperatures were studied to discuss the effects of the warm forming temperature. Through finite element analysis, the simulations of the axial-pushed incremental rolling process were carried out to investigate the effects of the warm forming temperature on rolling forces. The results indicated that the axial and radial forces on the rolling dies were both reduced at the warm forming temperature. Finally, the experiment studies were carried out on a warm axial-pushed incremental rolling equipment. The dimensional precision, microstructure, and hardness of the formed spline shafts at warm temperature were compared with those of the formed spline shafts at room temperature. The results indicated that the spline shafts, which were formed at the warm temperature, possesses of a good dimensional precision and excellent performance. The results in this paper demonstrated that the warm forming temperature has the positive effects on the performance improvement of the axial-pushed incremental rolling process of spline shaft. [ABSTRACT FROM AUTHOR]

According to the characteristics of news events, the clustering classification method is suitable such news events. However, traditional Single-Pass methods have two major drawbacks: low-level time efficiency and accuracy. In this paper, we focus on the clustering characteristics of news events, and propose a new method based on staging incremental Single-Pass. Firstly, the Vector Space Model (VSM) is used to represent the text vectors, and regression analysis is performed by using the Term Frequency and Inverse Documentation Frequency TFIDF weighting equation to establish the weighted calculation model. Meanwhile, the centroid vectors are used to represent news events models. Secondly, segmented lists are applied to news events models. Lastly, the cosine values of the angles are used to calculate the levels of similarity, and a similarity-based approach is used to realize the clustering of news events, and to selectively and dynamically update the segmented lists and centroid vectors so that the timeliness and accuracy of clustering could be significantly improved. Empirical experiments have demonstrated that the proposed method is effective, and could be used to improve clustering accuracy and reduce event complexity. [ABSTRACT FROM AUTHOR]

Hydraulic overpressure can induce fractures and increase permeability in a range of geological settings, including volcanological, glacial and petroleum reservoirs. Here we consider an example of induced hydraulic fracture stimulation in a tight-gas sandstone. Successful exploitation of tight-gas reservoirs requires fracture networks, either naturally occurring, or generated through hydraulic stimulation. The study of seismic anisotropy provides a means to infer properties of fracture networks, such as the dominant orientation of fracture sets and fracture compliances. Shear wave splitting from microseismic data acquired during hydraulic fracture stimulation allows us to not only estimate anisotropy and fracture properties, but also to monitor their evolution through time. Here, we analyse shear wave splitting using microseismic events recorded during a multistage hydraulic fracture stimulation in a tight-gas sandstone reservoir. A substantial rotation in the dominant fast polarization direction (ψ) is observed between the events of stage 1 and those from later stages. Although large changes in ψ have often been linked to stress-induced changes in crack orientation, here we argue that it can better be explained by a smaller fracture rotation coupled with an increase in the ratio of normal to tangential compliance (ZN/ZT) from 0.3 to 0.6. ZN/ZT is sensitive to elements of the internal architecture of the fracture, as well as fracture connectivity and permeability. Thus, monitoring ZN/ZT with shear wave splitting can potentially allow us to remotely detect changes in permeability caused by hydraulic stimulation in a range of geological settings. [ABSTRACT FROM AUTHOR]

• Aberrant expression of miR-26 can be detected in various kinds of malignant tumors. • The expression of miR-26 is regulated at four levels: gene amplification or LOH, SNP, transcriptional regulation, estrogen etc. • miR-26's validated target genes are involved in metabolism, proliferation, differentiation, apoptosis, invasion and metastasis of tumor cells. • miR-26 plays important roles in tumorigenesis and development. The microRNA-26 family, including miR-26a, miR-26b, miR-1297 and miR-4465, is a group of broadly conserved small RNAs with identical sequences at the seed region. The expression of miR-26 could be induced by hypoxia via a HIF-dependent mechanism, and up-regulated during multiple cell differentiation. Accumulating studies have demonstrated that miR-26 family members could be detected in many different kinds of tumors, and their validated target genes are involved in cell metabolism, proliferation, differentiation, apoptosis, invasion and metastasis. The expression of miR-26 might be a potentially valuable biomarker and a new target for cancer therapy. In this review, miR-26 family and its target genes in tumorigenesis and development will be summarized as follows. [ABSTRACT FROM AUTHOR]

A novel combined cooling and power (CCP) system utilizing liquefied natural gas (LNG) cryogenic energy and low-temperature waste heat was presented. The proposed system consists of two subsystems, absorption refrigeration/power cycle (ARP) subsystem and LNG refrigeration/power cycle (LRP) subsystem. The Rankine cycle and absorption refrigeration cycle were connected in series to form the ARP and they showed mutual enhancement in the integration. The operating performance of the system was calculated and analyzed. And the effects of generator pressure and circulation ratio on the performance were analyzed. Furthermore, a typical application case, in which the proposed system is integrated into the gas-steam combined cycle system as an LNG pre-processing and power enhancement unit, had been studied. The results showed that the net power generation efficiency, comprehensive energy utilization ratio, and exergy efficiency of the proposed CCP system reached 32.70%, 81.63%, and 35.14%, respectively. The feasibility and performance of the integrated system with combined cycle gas turbine were proved. And suggestions for the parameter design were presented. • A cogeneration system is proposed to utilize LNG cryogenic energy and waste heat. • Rankine cycle and absorption refrigeration cycle are combined in series. • Net power generation efficiency and exergy efficiency reach 32.70% and 35.14%. • Suggestions for system design are presented. • The integration with combined cycle gas turbine greatly improves performance. [ABSTRACT FROM AUTHOR]

• A combined cycle system with intermediate recuperated gas turbine is proposed. • The load range of constant turbine inlet temperature operating mode is extended. • Gas turbine and combined cycle part-load efficiency is improved by 2.15% and 1.04%. • Effects of pressure drop and minimum recuperative flow on performance are analyzed. In order to improve the performance of the combined cycle gas turbine (CCGT) under off-design conditions, an intermediate recuperated combined cycle gas turbine (IRCCGT) system was proposed, which was designed to suppress turbine inlet temperature (TIT) from decreasing as the load drops. In this system, a heat exchanger is installed between the third and fourth turbine stages, wherein a portion of the exhaust from the third turbine stage was used to heat the compressed air. In addition, the system-based operation strategy (maximizing the load range that employs constant TIT operation mode) was also analyzed. The results indicate that the TIT can be maintained at the design value until the gas turbine power load is reduced to 49% of the design value. When the inlet guide vane (IGV) angle reached the minimum value, the IRCCGT system increased gas turbine efficiency and combined cycle electrical efficiency by 4.7 and 3.1 percentage points. At the same gas turbine (GT) load, the maximum gains of GT efficiency and combined cycle efficiency were 2.15 and 1.04 percentage points, respectively. The pressure drops in the recuperator had a great impact on system performance, while the minimum recuperative mass flow rate had little effect. Overall, the proposed IRCCGT system can reduce the slope of the efficiency and load curve and improve the operating performance of the system under off-design conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A monolithic column‐based mass spectrometry (MS) analysis kit was prepared for whole blood analysis with MS. The kit is disposable and can be used for purification, storage, transportation and direct analysis of whole blood. The kit mainly consists of a capillary for quantitative microsampling, a cation exchange monolithic column for purification and storage, and a syringe for loading sample. This kit is very friendly to various users that one can easily siphon the blood in the kit followed by rapid clean‐up. We established a quantitative method using the kit with a limit detection as low as 0.33 nmol/L, and achieved more than five orders of magnitude enhancement in sensitivity compared to direct nanoelectrospray ionization MS analysis. The column can avoid analyte exposure to environment, which helps the storage of the sample for laboratory analysis. The relative standard deviation of immediate blood analysis and storage blood analysis within 10 d was less than 10%. This method has been successfully applied to the quantitative analysis of procainamide hydrochloride in 2 μL rat blood. These results indicate that this disposable kit does have the potential to achieve highly sensitive quantitative MS analysis in biological samples, which is expected to become a cost‐effective and powerful tool for in vitro diagnostics. [ABSTRACT FROM AUTHOR]