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Despite their crucial role in determining the fate of seeds, the type and breaking mode of seed dormancy in peatland plants in temperate Asia with a continental monsoon climate are rarely known. Fifteen common peatland plant species were used to test their seed germination response to various dormancy‐breaking treatments, including dry storage (D), gibberellin acid soaking (GA), cold stratification (CS), warm followed cold stratification (WCS), GA soaking + cold stratification (GA + CS) and GA soaking + warm followed cold stratification (GA + WCS). Germination experiment, viability and imbibition test, and morphological observation of embryos were conducted. Of the 15 species, nine showed physiological dormancy (PD), with non‐deep PD being the dominant type. Four species, Angelica pubescens, Cicuta virosa, Iris laevigata, and Iris setosa exhibited morphophysiological dormancy. Two species, Lycopus uniflorus and Spiraea salicifolia, demonstrated nondormancy. Overall, the effect hierarchy of dormancy‐breaking is: CS > GA > WCS > GA + CS > D > GA + WCS. Principal component analysis demonstrated that seed traits, including embryo length: seed length ratio, seed size, and monocot/eudicot divergence, are more likely to influence seed dormancy than environmental factors. Our study suggests that nearly 90% of the tested peatland plant species in the Changbai Mountains demonstrated seed dormancy, and seed traits (e.g. embryo‐to‐seed ratio and seed size) and abiotic environmental factors (e.g. pH and temperature seasonality) are related to germination behavior, suggesting seed dormancy being a common adaptation strategy for the peatland plants in the temperate montane environment. [ABSTRACT FROM AUTHOR]

From August 2010 to August 2020, there were 3 cases of pathologically diagnosed alveolar adenoma (AA) were reported in Peking Union Medical College Hospital so far, which was a rare benign neoplasm of the lung. The clinical manifestations and radiological characteristics on computer tomography of AA were heterogenous among these patients and lacked specificities. The difficulty in predictive differentiation of benign or malignant characteristic of the lesion led to some confusions in clinical practices. This paper reported 2 cases of AA and reviewed the literature of AA. Its clinical, radiographical and pathological characters were analyzed, so to provide more knowledge and improve the differential diagnosis of this disease.

Extensive areas in China have been receiving high levels of acid rain. Acid rain affects plant growth by reducing the chlorophyll content, destroying leaf structure, and hindering photosynthesis. Acer ginnala Maxim. has a high economic, ornamental, and medicinal value. To clarify the acid rain resistance mechanism of maple trees, the chlorophyll content, gas exchange parameters, and chlorophyll fluorescence parameters were measured in the leaves of 2-year-old Acer ginnala seedlings 0,15, and 30 days after simulated acid rain at pH 5.6, 5.0, 4.5, 4.0, 3.5, and 2.5. The results showed that the relative content of chlorophyll gradually decreased with the increasing acidity. The net photosynthetic rate ([P.sub.n]) decreased with the increasing acidity, and the difference among the treatments was significant except for between pH 5.0 and the control. The stomatal conductance at pH < 5.0 was significantly lower than that of the control, and the intercellular carbon dioxide (C[O.sub.2]) concentration of the leaves with the pH < 4.5 treatments was significantly lower than that of the control. As the acidity increased, both [F.sub.v]/[F.sub.m] and [F.sub.v]/[F.sub.0] ([F.sub.v], variable fluorescence; [F.sub.m], maximum fluorescence; [F.sub.0], initial fluorescence) decreased. The difference in the photosynthetic performance index based on the absorbed light energy ([PI.sub.abs]) between the pH 5.0 treatment and the control was not significant during the three periods after the simulated acid rain stress, whereas in the other treatments, this index was significantly lower than that of the control. Our results indicated that under mild acid rain (pH > 4.0) stress, the chlorophyll content, gas exchange parameters, and chlorophyll fluorescence parameters of Acer ginnala changed little, whereas in the other treatments, especially the severe acid rain (pH < 3.0) treatment, these indices showed significant changes that had a severe impact on plant growth and development. Key words: acid rain, Acer ginnala, chlorophyll fluorescence parameters, gas exchange parameters. En Chine, de vastes etendues reqoivent de fortes quantites de pluies acides. Les pluies acides sont nefastes pour la croissance des plantes parce qu'elles reduisent la teneur en chlorophylle, detruisent la structure des feuilles et nuisent a la photosynthese. Acer ginnala Maxim. a une grande valeur economique, ornementale et medicinale. Dans le but de clarifier le mecanisme de defense des erables aux pluies acides, la teneur en chlorophylle, les parametres des echanges gazeux et les parametres de fluorescence de la chlorophylle ont ete mesures dans les feuilles de semis d'Acer ginnala ages de 2 ans 0,15 et 30 jours apres avoir ete exposes a des pluies acides simulees avec un pH de 5,6, 5,0, 4,5, 4,0, 3,5 et 2,5. Les resultats montrent que la teneur relative en chlorophylle diminuait graduellement avec l'augmentation de l'acidite. Le taux de photosynthese nette ([P.sub.n]) diminuait avec l'augmentation de l'acidite et la difference entre les traitements etait significative sauf a pH 5,0 et dans le cas du temoin. Dans le cas de pluies acides avec un pH < 5,0 la conductance stomatique etait significativement plus faible que celle du temoin, tandis que dans les traitements avec un pH < 4,5 la concentration intercellulaire de C[O.sub.2] des feuilles etait significativement plus faible que celle du temoin. A mesure que l'acidite augmentait, [F.sub.v]/[F.sub.m] et [F.sub.v]/[F.sub.0] ([F.sub.v], [F.sub.m] et [F.sub.0] : fluorescence variable, maximum et initiale) diminuaient. La difference dans la valeur de l'indice de performance photosynthetique base sur l'energie lumineuse absorbee ([PI.sub.abs]) entre le traitement a pH 5,0 et le temoin n'etait pas significative durant les trois periodes suivant le stress cause par les pluies acides simulees, tandis que cette valeur etait significativement plus faible que celle du temoin dans le cas des autres traitements. Nos resultats indiquent que dans des conditions de stress du a des pluies legerement acides (pH > 4,0), la teneur en chlorophylle, les parametres des echanges gazeux et les parametres de fluorescence de la chlorophylle d'Acer ginnala ont peu change tandis que dans les autres traitements, surtout dans le traitement avec des pluies tres acides (pH < 3,0), ces indices ont subi d'importants changements qui ont eu de graves repercussions sur la croissance et le developpement des plants. [Traduit par la Redaction] Mots-cles: pluies acides, Acer ginnala, parametres de fluorescence de la chlorophylle, parametres des echanges gazeux., Introduction Acid rain has become an issue of great concern in the world during the past few decades (Abbasi et al. 2013). Studies conducted in recent years show that acid [...]

SUMMARY: Cryptotaenia japonica, a traditional medicinal and edible vegetable crops, is well‐known for its attractive flavors and health care functions. As a member of the Apiaceae family, the evolutionary trajectory and biological properties of C. japonica are not clearly understood. Here, we first reported a high‐quality genome of C. japonica with a total length of 427 Mb and N50 length 50.76 Mb, was anchored into 10 chromosomes, which confirmed by chromosome (cytogenetic) analysis. Comparative genomic analysis revealed C. japonica exhibited low genetic redundancy, contained a higher percentage of single‐cope gene families. The homoeologous blocks, Ks, and collinearity were analyzed among Apiaceae species contributed to the evidence that C. japonica lacked recent species‐specific WGD. Through comparative genomic and transcriptomic analyses of Apiaceae species, we revealed the genetic basis of the production of anthocyanins. Several structural genes encoding enzymes and transcription factor genes of the anthocyanin biosynthesis pathway in different species were also identified. The CjANSa, CjDFRb, and CjF3H gene might be the target of Cjaponica_2.2062 (bHLH) and Cjaponica_1.3743 (MYB). Our findings provided a high‐quality reference genome of C. japonica and offered new insights into Apiaceae evolution and biology. Significance Statement: Our results indicated how the genome of C. japonica provided a useful model for studying evolutionary trajectory and biological properties in Apiaceae species. Our findings are helpful for enriching genome research of Apiaceae family. [ABSTRACT FROM AUTHOR]

In order to study the influence of scanning strategy on the printing quality and properties of the formed parts,unidirectional scanning along one axis (X-scan),unidirectional scanning with 90° rotation in each layer (XY-scan),strip partition scanning strategy with direction changes in each layer (S-scan), checkerboard partition scanning strategy with direction changes in each layer (C-scan) were chosen to print 18Ni300 maraging steel by selective laser melting (SLM) process.The effects of different scanning strategies on the surface morphology, relative density,microstructure and mechanical properties of printed parts were studied systematically. The anisotropy of tensile properties of different scanning strategies in different forming directions was analyzed. The results show that the print quality and properties of the partition scanning strategies are better than that of X scanning strategy and XY scanning strategy. The reason is that during the printing process, the partition scanning strategy can divide each layer of laser scanning into multiple areas for printing, which improves the condensing rate for each layer. Compared with X scanning strategy and XY scanning strategy, the scanning direction of the partition scanning strategy changes periodically, which not only helps to fill the bulge and lap gap of the upper layer, but also reduces the heat accumulation and improves the performance of the sample.