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            Exceptionally well-preserved impression fossils of Cyrillopteris (ex. Odontopteris) orbicularis (Halle) comb. et emend. nov. have been described from the lower part of the middle–upper Permian Upper Shihezi (Upper Shihhotse) Formation in Yangquan City, Shanxi Province, North China. For the first time, this typical Cathaysian seed fern is confirmed to have a bipartite frond with two bipinnate branches, comparable with that of C. genuina (Grand’Eury) Laveine et Oudoire from the Pennsylvanian of France. Entire-margined cyclopteriod elements occur in the proximal portion of the long petiole. With increasing proximity of the bifurcation, the cyclopteroid elements progressively differentiate into pinnae with individual pinnules. True intercalary pinnules, which would be fully inserted on the primary rachides, are not present. Characteristics of our new specimens provide new information on the frond architecture of C. orbicularis (Halle) comb. et emend. nov., and allow a relatively complete circumscription of the overall features of this taxon, an emendation of the species diagnosis, and the presentation of an accurate frond reconstruction. Specimens of C. orbicularis comb. et emend. nov. are preserved with mesophytes and xerophytes from the same interval, demonstrating the vegetation in the research area grew under a seasonal subhumid to semiarid climates during the late Guadalupian.more » « less
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            Abstract. Oxygenated organic molecules (OOMs) play an important role in the formation of atmospheric aerosols. Due to various analytical challenges with respect to measuring organic vapors, uncertainties remain regarding the formation and fate of OOMs. The chemical ionization Orbitrap (CI-Orbitrap) mass spectrometer has recently been shown to be a powerful technique that is able to accurately identify gaseous organic compounds due to its greater mass resolution. Here, we present the ammonium-ion-based CI-Orbitrap (NH4+-Orbitrap) as a technique capable of measuring a wide range of gaseous OOMs. The performance of the NH4+-Orbitrap is compared with that of state-of-the-art mass spectrometers, including a nitrate-ion-based chemical ionization atmospheric pressure interface coupled to a time-of-flight mass spectrometer (NO3--LTOF), a new generation of proton transfer reaction-TOF mass spectrometer (PTR3-TOF), and an iodide-based CI-TOF mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (I−-CIMS). The instruments were deployed simultaneously in the Cosmic Leaving OUtdoors Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN) during the CLOUD14 campaign in 2019. Products generated from α-pinene ozonolysis under various experimental conditions were simultaneously measured by the mass spectrometers. The NH4+-Orbitrap was able to identify the widest range of OOMs (i.e., O ≥ 2), from less-oxidized species to highly oxygenated organic molecules (HOMs). Excellent agreement was found between the NH4+-Orbitrap and the NO3--LTOF with respect to characterizing HOMs and with the PTR3-TOF for the less-oxidized monomeric species. OOM concentrations measured by NH4+-Orbitrap were estimated using calibration factors derived from the OOMs with high time-series correlations during the side-by-side measurements. As with the other mass spectrometry techniques used during this campaign, the detection sensitivity of the NH4+-Orbitrap to OOMs is greatly affected by relative humidity, which may be related to changes in ionization efficiency and/or multiphase chemistry. Overall, this study shows that NH4+-ion-based chemistry associated with the high mass resolution of the Orbitrap mass analyzer can measure almost all inclusive compounds. As a result, it is now possible to cover the entire range of compounds, which can lead to a better understanding of the oxidation processes.more » « less
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            This paper studies the relationships between network capabilities and innovation development in the context of two types of innovation networks: scientific knowledge networks (SKN) and technological knowledge networks (TKN). Focusing on two types of network capabilities, namely acquisition capability and control capability, the paper uses spatial regime models to compare the impacts of multiple factors on different spatial regimes. The main conclusions are the following. First, as regards SKN, the political-administrative hierarchy has shaped the spatial evolution of acquisition capacity, forming a pattern consisting of three dominant cities (Beijing, Shanghai, Nanjing), three subsidiary cities (Guangzhou, Hangzhou, Wuhan), and multiple lesser centers (Tianjin, Chengdu, Xi’an). Moreover, high control capability cities are mainly clustered in the coastal areas, specifically, one monocentric city (Beijing) and two polycentric metropolises (Shanghai, Wuhan). Second, for TKN, cities with high acquisition and control also are mainly found in coastal areas, with Shanghai and Beijing dominating network capabilities. The model’s analysis confirms the positive effect of network capabilities on innovation development, especially in scientific knowledge networks, and the driver for regional innovation development appears to have shifted from global pipeline (globalization) to local buzz (localized talents). This paper concludes with suggestions regarding network capabilities’ potential to reduce regional inequality and achieve sustainable development of regional economies.more » « less
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