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Currently, China has 32 Earth observation satellites in orbit. The satellites can provide various data such as optical, multispectral, infrared, and radar. The spatial resolution of China Earth observation satellites ranges from low to medium to high. The satellites possess the capability to observe across multiple spectral bands, under all weather conditions, and at all times. The data of China Earth observation satellites has been widely used in fields such as natural resource detection, environmental monitoring and protection, disaster prevention and reduction, urban planning and mapping, agricultural and forestry surveys, land survey and geological prospecting, and ocean forecasting, achieving huge social benefits. This article introduces the recent progress of Earth observation satellites in China since 2022, especially the satellite operation, data archiving, data distribution and data coverage.

Rape (Brassica napus) is an important oilseed crop widely cultivated worldwide. Due to its relatively short evolutionary and domestication history, its intra-species genetic diversity is limited. Radish (Raphanus sativus), belonging to a different genus but the same family as B. nupus, possesses an abundance of excellent gene resources. It is commonly used for B. nupus germplasm improvement and genetic basis expansion, making it one of the most important close relatives for distant hybridization. In the present study, a novel method for detecting alien chromosome fragments, called Anchor Mapping of Alien Chromosome (AMAC) was used to identify radish chromosome segments in the progeny of rape–radish interspecific hybrids. Based on the AMAC method, 126,861 pairs of IP (Intron Polymorphism) and 76,764 pairs of SSR (Simple Sequence Repeat) primers were developed using the radish Rs1.0 reference genome. A total of 44,176 markers (23,816 pairs of IP and 20,360 pairs of SSR markers) were predicted to be radish genome specific-single-locus (SSL) markers through electronic PCR analysis among four R. sativus, one B. napus, one B. rapa, one B. juncea, and one B. juncea reference genome. Among them, 626 randomly synthesized SSL markers (478 SSL IP markers and 148 SSL SSR markers) were used to amplify the genome of 24 radish samples (R. sativus), 18 rape (B. napus), 2 Chinese cabbage (B. rapa), 2 kale (B. oleracea), and 2 mustard (B. juncea) samples, respectively. Then, 333 SSL markers of the radish genome were identified, which only amplified in the radish genome and not in any Brassica species genome, including 192 IP markers and 141 SSR markers. Furthermore, these validated SSL markers were used to identify alien chromosome fragments in Ogura-CMS restorer line 16C, Ogura-CMS sterile line 81A, and their hybrid-Yunyouza15. In 16C, one marker, Rs1.0025823_intron_3, had an amplification product designated as anchor marker for the alien chromosome fragment of 16C. Afterwards, four novel radish genome-specific IP markers were found to be flanking the anchor marker, and it was determined that the alien chromosome segment in 16C originated from the region 8.4807–11.7798 Mb on radish chromosome R9, and it was approximately 3.2991 Mb in size. These results demonstrate that the AMAC method developed in this study is efficient, convenient, and cost-effective for identifying excellent alien chromosome fragments/genes in distant hybrid progeny, and it can be applied to the molecular marker-assisted breeding and hybrid identification of radish and Brassica crop species. [ABSTRACT FROM AUTHOR]

Here we aimed to define the prevalence of imposter syndrome (IS) and identify associated characteristics in Chinese medical students and residents enrolled at Peking Union Medical College Hospital (PUMCH). This was a single-center, cross-sectional study of medical students and residents enrolled at PUMCH conducted in September and October 2022. Participants were recruited to complete a 37-question survey on demographics, a Chinese version of the Clance Imposter Phenomenon Scale (CIPS), and self-assessments of anxiety, depression, burnout, sleep quality, challenges of clinical learning, and time allocation. IS prevalence and its associated factors were analyzed. One hundred and forty-eight medical students and 89 residents completed the survey. IS was significant or severe in 62.8% of medical students and 57.2% of residents. Students enrolled in the eight-year program had significantly higher CIPS scores than those enrolled in the 4 + 4 program (66.4 vs. 60.7, p =.005). There were no gender differences in IS prevalence and severity. Participants with severe IS had significantly higher self-rated anxiety, depression, insomnia, and burnout than participants with mild/moderate IS. Participants significantly challenged by clinical learning had significantly higher CIPS scores. IS is both prevalent and severe in Chinese medical students and residents. Classroom learning, an eight-year program, and being challenged by clinical learning are potentially associated with IS. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs) can be used as biomarkers for acute myocardial infarction (AMI). However, few reports have focused on the value of exosomal miRNAs in the mechanism of the pathophysiological process from stable coronary artery disease (SCAD) to AMI. Exosomes were isolated via ultracentrifugation after serum samples were collected. The exosomes were then identified by transmission electron microscopy, western blotting, and nanoparticle tracking analysis. The differential expression of miRNAs in exosomes from six AMI and six matching SCAD patients was screened using the Agilent Human miRNA Microarray Kit. Target genes of the candidate miRNAs were predicted via an online miRNA database, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analyses. Further validation was conducted through quantitative real‐time polymerase chain reaction with 60 exosome samples. The expression of 13 miRNAs was significantly downregulated in the AMI samples compared with the SCAD samples. In addition, we identified various target genes that are mainly involved in the pathways of cardiac rehabilitation and remodelling. Validation of the expression of candidate miRNAs indicated that exosomal miR‐1915‐3p, miR‐4,507, and miR‐3,656 were significantly less expressed in AMI samples than in SCAD samples, and area under the receiver‐operating‐characteristic curve (AUC) analysis showed that the expression of these miRNAs resulted in good predictive accuracy [miR‐1915‐3p (AUC: 0.772); miR‐4,507 (AUC: 0.684); and miR‐3,656 (AUC: 0.771)], suggesting that these serum exosomal miRNAs might be predictive for AMI at an early stage. Hence, exosomal miRNAs might play an important role in the pathophysiology of AMI and could serve as diagnostic biomarkers. [ABSTRACT FROM AUTHOR]

In 2016, unambiguous evidence for the presence of the amino acid glycine, an important prebiotic molecule, was deduced based on in situ mass-spectral studies of the coma surrounding cometary ice. This finding is significant because comets are thought to have preserved the icy grains originally found in the interstellar medium prior to solar system formation. Energetic processing of cosmic ices via photochemistry and radiation chemistry is thought to be the dominant mechanism for the extraterrestrial synthesis of prebiotic molecules. Radiation chemistry is defined as the “study of the chemical changes produced by the absorption of radiation of sufficiently high energy to produce ionization.” Ionizing radiation in cosmic chemistry includes high-energy particles (e.g., cosmic rays) and high-energy photons (e.g., extreme-UV). In contrast, photochemistry is defined as chemical processes initiated by photon-induced electronic excitation not involving ionization. Vacuum-UV (6.2–12.4 eV) light may, in addition to photochemistry, initiate radiation chemistry because the threshold for producing secondary electrons is lower in the condensed phase than in the gas phase. Unique to radiation chemistry are four phenomena: (1) production of a cascade of low-energy (＜20 eV) secondary electrons which are thought to be the dominant driving force for radiation chemistry, (2) reactions initiated by cations, (3) non-uniform distribution of reaction intermediates, and (4) non-selective chemistry leading to the production of multiple reaction products. The production of low-energy secondary electrons during radiation chemistry may also lead to new reaction pathways not available to photochemistry. In addition, low-energy electron-induced radiation chemistry may predominate over photochemistry because of the sheer number of low-energy secondary electrons. Moreover, reaction cross-sections can be several orders of magnitude larger for electrons than for photons. Discerning the role of photochemistry vs. radiation chemistry in astrochemistry is challenging because astrophysical photon-induced chemistry studies have almost exclusively used light sources that produce ＞10 eV photons. Because a primary objective of chemistry is to provide molecular-level mechanistic explanations for macroscopic phenomena, our ultimate goal in this review paper is to critically evaluate our current understanding of cosmic ice energetic processing which likely leads to the synthesis of extraterrestrial prebiotic molecules. [ABSTRACT FROM AUTHOR]

Objective: We report on the clinical characteristics, treatments and outcomes of Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuritis (CIDP) associated with SLE., Methods: Patients treated at Peking Union Medical College Hospital between January 2004 and November 2021 who fulfilled the diagnostic criteria for SLE and GBS/CIDP (n=9) were included. Clinical presentations, lab results, treatment regimens and prognoses were retrieved and analysed., Results: Six patients were diagnosed with SLE and GBS, while three were diagnosed with SLE and CIDP, with the average age at diagnosis of 38.6±18.2 years. SLE disease duration ranges from 1 week to 36 years, and the courses of GBS and CIDP range from 1 week to 2 months and from 2 months to 15 months, respectively. All patients exhibited either or both limb paresthesia and weakness, other neurological symptoms include dysphagia, peripheral facial nerve palsy and respiratory and cardiac arrest. The median cerebral spinal fluid white blood cell count and protein level were 0.002×10 9 /L (0-0.006×10 9 /L) and 0.79 g/L (0.57-7.09 g/L), respectively. All patients received glucocorticoid and immunoglobulin therapy. Seven patients received cyclophosphamide, and seven patients received intrathecal injections of methotrexate and dexamethasone. Two patients had complete resolution, five experienced marked improvements and two failed to improve with treatments., Conclusion: SLE-associated GBS/CIDP may manifest regardless of disease systemic activity. Clinical features may differ from that of pure GBS/CIDP, and treatment often requires immunosuppressants, making differential diagnosis crucial, especially for patients with GBS/CIDP presenting as the first manifestation of SLE., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The profiling of plasma cell-free DNA (cfDNA) is becoming a valuable tool rapidly for tumor diagnosis, monitoring and prognosis. Diverse plasma cfDNA technologies have been in routine or emerging use, including analyses of mutations, copy number alterations, gene fusions and DNA methylation. Recently, new technologies in cfDNA analysis have been developed in laboratories, and potentially reflect the status of epigenetic modification, the immune microenvironment and the microbiome in tumor tissues. In this review, the authors discuss the principles, methods and effects of the current cfDNA assays and provide an overview of studies that may inform clinical applications in the near future., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare., (Copyright ©2021Chinese Journal of Cancer Research. All rights reserved.)