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Introduction: Distinguishing and categorizing the origin of garlic are highly significant, considering its widespread use as a flavoring agent. With billions of dollars annually in global trade, garlic is frequently susceptible to fraudulent practices. Methodology: Paper spray ionization mass spectrometry (PS‐MS) was employed to quickly analyze garlic samples from distinct geographic origins: China and Brazil. The so‐generated PS‐MS data were treated with metabolomic multivariate approaches, and the garlic samples from these different geographic regions were easily discriminated. Results: Brazilian garlic was characterized to contain higher levels of amino acids, such as arginine, proline, and valine, and organosulfur compounds, such as allicin, alliin, and l‐γ‐glutamil‐S‐allyl‐l‐cysteine, compared to Chinese garlic. The PS‐MS data were treated employing multivariate approaches, typically used in the metabolomics field, and this protocol was promptly able to discern among both types of samples. Conclusion: Hence, this combined strategy holds promise not only as an effective tool for the authentication of the geographical origin of garlic but also as a powerful means for biomarker discovery. [ABSTRACT FROM AUTHOR]

Coeval Neoproterozoic mafic dykes with a well‐constrained isotopic age of 925 Ma are distributed in the North China Craton (NCC) of China and São Francisco Craton (SFC) of Brazil. Several recent studies favor the hypothesis that these two cratons were connected during 925 Ma and constituted building cratons for the supercontinent Rodinia. However, the paleo‐positions of the two cratons in Rodinia have not yet been paleomagnetically resolved. This paper presents the paleomagnetic results of these dykes in both NCC and SFC. Detailed thermal and alternating‐field demagnetization revealed that these dykes record stable components of magnetization with unblocking temperatures below the Curie temperature of magnetite. Rock magnetic results and scanning electron microscope analysis further confirm that the major magnetic minerals in dyke samples are pseudo‐single domain titanomagnetites. The mean directions of the characteristic remanent magnetization (ChRM) of the dykes are distinct from those of rocks of different ages in the sampling localities, and are supported by positive baked contact tests, indicating primary remanent magnetization. The ChRM of the SFC dykes also exhibits dual polarity. Our results suggest that the NCC and SFC were in the moderate to high paleolatitudes of the Southern Hemisphere during approximately 925 Ma, suggesting a possible paleogeographic connection between the two cratons. A new paleogeographic reconstruction of both cratons during 925 Ma is proposed, which is supported by other geological evidence. Plain Language Summary: The formation and breakup of the supercontinent Rodinia have played crucial roles in the global tectonic evolution and paleoclimate changes during the Neoproterozoic which lasted from 1.0 billion to 541 million years ago. The exact configuration of the Rodinia remains debatable, including whether the North China Craton (NCC) and São Francisco Craton (SFC) were integral components of the Rodinia. In this paper, we present new results of an integrated investigation, including paleomagnetic and rock magnetic studies and scanning electron microscope analysis, on the well dated coeval 925 Ma mafic dykes in both NCC and SFC. The results of scanning electron microscope and magnetic measurements confirm the major magnetic minerals and the stability of characteristic remanence directions. The results imply that both NCC and SFC were located at moderate to high paleolatitudes of the Southern Hemisphere during approximately 925 Ma, suggesting the possibility of a paleogeographic connection between the two cratons in the Rodinia. The findings of this study help gain improved understanding of paleogeography of the early Earth. Key Points: Characteristic remanence for the 925 Ma dykes in North China Craton and São Francisco Craton is interpreted as primaryBoth cratons were located at moderate–high paleolatitudes, southwest of Rodinia's core at 925 Ma, suggesting a paleogeographic connectionThe possible paleogeographic connection between the two cratons is supported by new paleomagnetic and geological evidence [ABSTRACT FROM AUTHOR]

This paper estimates the impact of Brazilian soybean area expansion on US and Brazilian soybean exports to China by projecting these countries' exports for various Brazilian soybean area growth scenarios. The results indicate that the Brazilian area expansion does not significantly affect US soybean exports to China but positively impacts Brazil's soybean exports to China. Ex‐post analysis of the impacts of Chinese tariff during the US–China trade war indicates that China significantly diverted its imports from the United States to Brazil. We conclude that the US soybean trade policy should focus on mitigating the adverse effects of import demand changes. [ABSTRACT FROM AUTHOR]

Ionospheric scintillation could seriously disrupt the signal tracking of the global navigation satellite systems (GNSS), further causing positioning accuracy degradation or unavailability. BeiDou navigation satellite system (BDS), a newly developed GNSS by China, has begun to provide global positioning, navigation, and timing service. The objective of the present study is to investigate the effects of ionospheric scintillation on BDS‐2 and BDS‐3 multi‐frequency signals. Ionospheric scintillation monitor receiver data from four monitors in Brazil were collected from October 2021 to May 2022. The results illustrate that S4(B2) and S4(B3) linearly increase with S4(B1) for S4(B1) ≤ 0.6, which is consistent with weak scattering theories, and average experimental ratios of S4(B2)/S4(B1), S4(B3)/S4(B1), and S4(B2)/S4(B3) are less than corresponding theoretical ones by 6.1%, 4.4%, and 1.9%, respectively. Meanwhile, as S4 values increase, lower‐frequency scintillation saturates earlier than higher ones, and the probability of ionospheric scintillation events on B2 and B3 signals is approximately twice (S4 ≥ 0.7) as B1 signals in the equatorial ionization anomaly (EIA) regions. To alleviate the undesirable effects of missing data on GNSS positioning, we first investigate the inter‐frequency relationship and distribution probability of two significant spectral parameters, that is, T (the spectral strength of the phase noise at 1 Hz) and p (the spectral slope of the phase power spectral density) in the tracking jitter model among three BDS frequencies. Results show that the performances among B1, B2, and B3 frequencies have a higher correlation respectively, and their values for B2 and B3 signals are more susceptible to be impacted by ionospheric scintillation. Plain Language Summary: Ionospheric scintillation seriously affects the precision and continuity of the global navigation satellite systems (GNSS) signals and causes positioning accuracy degradation or unavailability. Therefore, it is essential to study the impacts of ionospheric scintillation on the GNSS receiver performance. This study first investigates the inter‐frequency relation of the amplitude scintillation index S4 for B1, B2, and B3 signals from BDS‐2 and BDS‐3 satellites based on the Ionospheric scintillation monitor receiver data at four geomagnetic latitudes in the Brazilian territory. Furthermore, the distribution probability and inter‐frequency relationship of two significant phase spectral parameters of the tracking jitter model, which are widely applied in GNSS positioning solutions, are also presented among three BDS frequencies. All investigations conducted within this contribution show agreement with earlier work in ionospheric scintillation and provide supportive and detailed numerical statements and comparisons. Key Points: The inter‐frequency relation of the amplitude scintillation index for multi‐frequency signals from BDS‐2 and BDS‐3 satellites is displayedThe probability of the ionospheric scintillation events on B2 and B3 signals is approximately twice (S4 ≥ 0.6) as B1 signals in EIA regionsThe spectral parameters p and T of B2 and B3 signals are more susceptible to be affected by ionospheric scintillation [ABSTRACT FROM AUTHOR]