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Latest exploration practices revealed appreciable petroleum resources in the deep pre-Cenozoic reservoirs in the southwest area of the Bozhong depression; however, the origins and accumulation mechanisms of deep hydrocarbons remain not fully understood. Here, an integrated study of the geochemical characteristics of overlying source rocks, maturity evaluation of petroleum, and origin of natural gas was conducted to characterize the dynamic petroleum accumulation and illustrate the main factors influencing the differential phases of petroleum distribution in the research area. The third member of the Dongying Formation (Ed3) mudstone in the research area displays high organic richness and is characterized by oil-prone organic matter, indicating high petroleum potential. The oils contained in the CFD18 and BZ13 buried-hill traps were mainly derived from the Ed3 and Shahejie Formation (Es) source rocks, respectively, with natural gas of kerogen cracking origin. Buried-hill oil from the BZ13 field displays a high thermal maturity than that of the CFD18 oils, which was evidenced by maturity parameters of saturated and aromatic hydrocarbons and concentrations of stigmastane. Nevertheless, maturity index of diamondoids and carbon isotopic composition of natural gas indicate the possible presence of mixing of higher mature Es fluids for the CFD18 field. This research underlines the contribution of the overlapped effective source rocks to the buried-hill traps. The causes of multiple petroleum phases in the deep reservoirs in the research area are mainly linked to dynamic petroleum accumulation rather than source rock type and oil secondary cracking. Although faults are present to act as vertical migration conduits due to late-stage activation with high intensity, abundant petroleum supply due to near-source charge and favorable constitution relationship of source rock and reservoir rock provide crucial conditions for deep petroleum accumulation in a tectonic activation zone.

Efforts to maximize seed or forage yield with nitrogen (N) fertilizer are common in cropping systems. However, only limited attention has been paid to investigate N fertilizer application in different seasons, especially for perennial grasses, whose seed production requires two or more growing seasons. We conducted a two-year field experiment to evaluate the impacts of N application timing (fall in previous year and spring in current year) and N application rate (0, 28 and 56 kg N ha −1 yr −1 ) on seed yield, forage production and N use efficiency for a semi-arid, perennial grass ( Leymus chinensis ). As compared to the spring N application, we found that fall N application at the inflorescence stage in the previous year significantly increased seed yield, forage yield, seed agronomic N use efficiency (s-aNUE), forage agronomic N use efficiency (f-aNUE), seed physiological N use efficiency (s-PE) and forage physiological N use efficiency (f-PE). Seed yield and forage yield were both higher with high N-rate treatment as compared to low N-rate in both years. Nitrogen rate effects on N use efficiency indices varied with year and N-timing. We conclude that N application in the fall of the previous year matches N demand for increases in seed yield and forage yield and this is an optimum choice to achieve greater seed yield and forage yield with high N use efficiency. Our research implies that N application in the fall increases inflorescence number and fall tillers by stimulating inflorescence and/or fall tillers numbers. Future research should focus on determining for each physiological stage that control the seed and/or forage yield components, the limiting resource. Then targeting the limiting resource at each physiological stage can increase yield, and, for perennial crops, the key stages regulating seed and/or forage yield components can be in different years, as we found for Leymus chinensis .

Neuroimaging studies have proposed specific brain regions for reading Chinese characters. For example, compared to alphabetic languages, Chinese reading has revealed more activation of the left Middle Frontal Gyrus (MFG) and null or deactivation at left posterior Superior Temporal Gyrus (pSTG). However, the model of specific regions for Chinese was contested by recent findings showing similar activities across languages under the same task demand. Thus, whether the engagement of the Chinese-specific regions was due to stimulus selectivity or to task demand was called into question. The current meta-analysis, using Activation Likelihood Estimation (ALE), summarized brain regions in previous fMRI studies from two types of contrast, stimulus contrasts (SC), in which more regions were activated for Chinese characters than for other visual stimuli (e.g., Korean words, faces) or for other types of characters (e.g., real > artificial characters), and task contrasts (TC), in which more regions were activated for one task than for another (e.g., lexical decision > symbol detection) in processing Chinese characters. ALE activation maps revealed a shared network for the two types of contrast, including the right Inferior Frontal Gyrus (IFG, BA47) and four clusters in the left hemisphere, the IFG (BA45/46), Superior Parietal Lobule, Superior Frontal Gyrus, and posterior Middle Temporal Gyrus (pMTG). The SC > TC comparison demonstrated the greater involvement of the left Angular Gyrus and left Fusiform Gyrus. The TC > SC comparison, in contrast, revealed the engagement of left-hemisphere regions in the IFG, MFG, pSTG, pMTG, and Medial Frontal Gyrus. These results suggest that the previously identified Chinese-specific areas (e.g., MFG, pSTG) might be task dependent rather than stimulus selective. This work shed light on the language-general neural network of visual word reading.

Ballistocardiography (BCG), the noninvasive measurement of the reaction forces of the body to the cardiac ejection of blood, is one of few methods available for unobtrusively assessing the mechanical aspects of cardiovascular health outside clinical settings. In this study, two sizes of piezoelectric film sensors were installed into the seat cushion of a chair and the foot insole, respectively, to acquire local BCG signals in sitting and standing positions. The design and engineering implementation of the signal processing circuit and data transmission system are discussed below. Although wearable BCG measurement devices have been extensively researched to date, to the authors’ knowledge, they have never been tested in regards to power consumption and electrostatic discharge (ESD) immunity. In this work, comprehensive experiments were conducted to show the low power consumption and high reliability of the proposed system. The shapes and the amplitudes of measured signals were examined in detail. The results suggest that the proposed system can feasibly and reliably be used to continuously record and evaluate cardiovascular changes occurring throughout an individual’s daily life.