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Objectives: During embryonic haematopoiesis, haematopoietic stem/progenitor cells (HSPCs) develop from hemogenic endothelial cells (HECs) though endothelial to haematopoietic transition (EHT). However, little is known about how EHT is regulated in human. Here, we report that GFI1 plays an essential role in enabling normal EHT during haematopoietic differentiation of human embryonic stem cells (hESCs). Results: GFI1 deletion in hESCs leads to a complete EHT defect due to a closed chromatin state of hematopoietic genes in HECs. Mechanically, directly regulates important signaling pathways essential for the EHT such as PI3K signaling.etc. Conclutions: Together, our findings reveal an essential role of GFI1 mediated epigenetic mechanism underlying human EHT during hematopoiesis. [ABSTRACT FROM AUTHOR]

The hare's fur glazed Jian wares characterized by radial fur-like strips, as one of the typical representatives of Chinese ceramics in the 10th-13th century (A.D.), were famous for the aesthetic values in highlighting the color sparkling effects of tea soup, which were one of the indispensable tea wares in tea culture. The firing technology of hare's fur glaze of Jian wares not only played a crucial role in the development of Chinese ceramic history, but also enlightened the modern imitation technology. The hare's fur glaze of Jian wares can be further grouped according to the color of strips, of which the yellowish-brown hare's fur glaze (yellowish-brown matte strips), gold hare's fur glaze (golden shiny strips) and silver hare's fur glaze (bright silvery strips) were the most representative types. Epsilon-Fe2O3, a specific metastable crystal phase, has become a research hotspot as the chromogenic crystals of hare's fur glaze, however, the comparative analysis focused on the correlation between ε-Fe2O3 and the macroscopic glaze color has been barely reported. In our work, the bright color strips (hare's fur area) and black strips (black glaze area) of silver, gold and yellowish-brown hare's fur glaze were morphologically and compositionally analyzed by SEM and EDS, respectively. The morphological features and compositional differences of three representative types of hare's fur glaze samples were summarized, which indicated the differences in the size, distribution and coverage of crystals and the distribution and contents of materials. It was speculated that high-level of Fe2O3 and CaO with low-level of SiO2 and Al2O3 may relate to the crystallization of ε-Fe2O3. This work helps in laying the foundation of further explanation of the technological differences of hare's fur glazes. [ABSTRACT FROM AUTHOR]

The world's first high‐fired glazes were made in China, probably in the 16th century BCE, based largely on siliceous clay and calcareous wood ash. By the Song Dynasty (960–1279), this technology was at its zenith and included blackware glazes that exhibited reddish‐brown single‐phase, micron‐scale ε‐Fe2O3 films on their surfaces. However, it has been difficult to synthesize and replicate this effect on a larger scale and to a higher degree of purity through modern synthetic methods. To fully understand this effect, a strategy that combines nanomaterial science methods and theoretical calculation has been developed to study the hare's fur glazes of Song Dynasty (960–1279) Jian wares. Through our study of the original Song glazes, we show that a high‐alumina clay was used in creating the glaze, which introduced Al into the ε‐Fe2O3 lattices, playing a crucial role in metastable crystal stabilization. The explanation of both Al‐doping from clay, combined with a new understanding of ancient but effective firing manipulation, may provide alternative approaches for materials synthesis. [ABSTRACT FROM AUTHOR]

In August 2014, a pit containing more than 10000 porcelain shards was excavated in the southwestern area of the Palace Museum. Reign marks and other stylistic criteria dated the manufacture of these fragments from the reign of Hongwu in the Ming Dynasty (1368–98 CE) to the Guangxu reign in the Qing Dynasty (1875–1908 CE). A famille rose (fencai, 粉彩) bowl decorated with a red-ground peony pattern and having the reign mark of Qianlong (1736–96 CE) on the base was studied using several non-destructive analytical methods to determine the variation in overglaze compositions, the colorants, the application sequences, the thickness of the colored layers and the high-temperature porcelain glaze, and the identification of the surface weathering products that formed during burial. The methods include non-destructive X-ray fluorescence, Raman spectroscopy, optical stereomicroscopy, and laser confocal microscopy, as well as X-ray diffraction. [ABSTRACT FROM AUTHOR]

Metastable ε-Fe2O3 was discovered on a ceramic ware of Deqing kiln of the Tang Dynasty, which coexists with α-Fe2O3 in the brown area between adjacent black glaze areas, and it is the earliest known artificially synthesized ε-Fe2O3. Based on the composition analysis of α-Fe2O3, ε-Fe2O3 and the glass phase around them, it is speculated that some Fe3+ ions were replaced by Al3+ ions during the formation of ε-Fe2O3, and a relatively low CaO content may be required for its crystallization. This work may promote researchers' understanding of ε-Fe2O3 crystals, and provide clues for the artificial synthesis of large ε-Fe2O3 crystals. [ABSTRACT FROM AUTHOR]

Changsha Kiln rose and flourished alongside the development of China's Maritime Silk Road (8th–9th century). The kiln occupies an important place in the development of China's ceramic science and technology, notably as the source of high-temperature copper-red glaze. A variety of lime-colored glaze was one product of Changsha Kiln. Its surface was decorated with both copper-green and copper-red, and is the earliest known example of the successful firing of a copper-red glaze. This ware is representative of the birth of high-temperature copper-red glaze, but there has been a lack of research on its optical properties and the technology's origin. In this paper, OM, SEM, TEM, optical coherence tomography (OCT), XRF, fiber optic spectrometry, and other analytical techniques were used to investigate the red and green glazes of Changsha Kiln. The key result of this paper is to reveal the optical properties of copper-green and copper-red in combination with colloidal absorption, ion absorption, and scattering, and to study the key factors for the origin of the high-temperature copper red glaze. [ABSTRACT FROM AUTHOR]

The Jingdezhen Imperial Kiln made unprecedented achievements in the firing of colour glazed porcelain during the Qing Dynasty (1636–1912). Among these, beige-glazed porcelain became an imperial porcelain variety reserved for the exclusive use of the imperial household. To reveal details of the manufacturing process, Energy Dispersive X-ray Fluorescence (EDXRF) and spectrophotometry, combined with the records of ancient Chinese documents were used to analyse samples of beige-glazed porcelain fired at the Jingdezhen Imperial Kiln in the early and middle Qing Dynasty (18th century) and unearthed from the Nandaku area of the Forbidden City. The results show that the colour of beige glaze in the Qing Dynasty was similar to that in the Song Dynasty (960–1279), which is consistent with ancient literature records reflecting the former's imitation of 'Beige Song Glaze'. The beige-glazed porcelain body is made of a binary formula of porcelain stone and kaolin clay, in a ratio between 5:5 and 4:6. Based on the glaze layer formula of purple-gold imperial porcelain, the beige glaze layer was fired by innovatively adjusting the ratio of glaze stone, glaze ash and purple-gold clay. The imitation of 'beige Song glaze' and the innovation of purple-gold glaze reflected the exacting production and high technology of the Jingdezhen Imperial Kiln in the Qing Dynasty. [ABSTRACT FROM AUTHOR]

The epigenetic treatment by 3-Deazaneplanocin A (DZNep), a histone methyltransferase inhibitor, shows great potential against acute myeloid leukemia (AML). However, the variant sensitivity and incomplete response to DZNep are commonly observed. Here, we reveal that vitamin C (Vc) dramatically promotes DZNep response against leukemic cells in different cell lines and primary AML samples. Vc enhances apoptosis and differentiation induced by DZNep in different AML cell lines in vitro and reduces leukemia progression in vivo. At the molecular level, Vc downregulates an enzyme of serine synthesis named D-3-phosphoglycerate dehydrogenase (PHGDH), as well as BCL2, an anti-apoptotic gene. Over-expression of PHGDH reverses the Vc-enhanced anti-leukemic effect of DZNep in AML cells. Therefore, our findings provide an effective approach to reduce the resistance against epigenetic treatment by Vc, which shows a potential improvement of their combination in AML patients. • Vc enhances anti-leukemia effect of DZNep in vitro and in vivo. • Vc promotes differentiation and maturation gene program in AML cells triggered by DZNep. • PHGDH is essential in Vc enhanced anti-leukemia effect of DZNep. [ABSTRACT FROM AUTHOR]

Tie luo (affixed hanging) was an expressive form of traditional Chinese calligraphy or paintings, and popular in the imperial palaces for interior decorations in Qing Dynasty (1644-1911 C.E.). A piece of calligraphic tie luo, written by an eminent calligrapher Gu Gao (1763-1832 C.E.), was restored recently in the Palace Museum, Beijing, China. The paper with pigment coating specially made for this calligraphic piece was named as fenjian. This article presented results from materials identification prior to the restoration. Multianalysis with scientific approaches revealed how tie luo was manufactured. It could be concluded that the investigated tie luo used a paper made from bast fibers of mulberry trees. And the decorative ground layer for the piece was also studied, which indicated that a type of organic red pigments were used for the masterpiece. White lead was considered as the main pigment, mixed with a red dye extracted from sappanwood. Meanwhile, animal glue, drying oils and beeswax were confirmed as the organic binding media. In dye analysis, protosappanin B and brazilin as well as brazilein were identified, which implied that sappanwood was used for the organic manufacture of pigments. In addition, both Nowik type A and C were found in the research, which were characteristic of sappanwood for identification. [ABSTRACT FROM AUTHOR]