Museum of Heilongjiang Province

Pisinnocaris subconigera was first described as a rare, small euarthropod from the early Cambrian Chengjiang biota, southwestern China. The taxonomic validity of this species was later challenged due to the lack of essential morphological details to differentiate it from Fuxianhuia protensa, especially from the juvenile perspective. Here, we examined the holotype and additional specimens of P. subconigera with multiple imaging techniques, such as microscope optical imaging, micro-CT scanning and computer-based 3D rendering, and revealed the previously unknown ventral organization of P. subconigera. New findings include four short prothoracic segments each bearing a pair of biramous appendages, four opisthothoracic segments each with four pairs of appendages, and four limbless abdominal segments. Both the small and large individuals exhibit unique and consistent morphological characteristics, indicating that P. subconigera does not represent the larval or juvenile form of any fuxianhuiid as previously proposed. Combined with phylogenetic analyses, our study suggests that P. subconigera remians as a valid member of the early Cambrian fuxianhuiids.

The Hanging Coffin represents a distinctive mortuary tradition practiced across southern China, Southeast Asia (e.g., the Log Coffin), and the Pacific approximately 3,000 years. Historical records attribute this funerary practice to the Bo people, a group that largely disappeared from documented history by the end of the Ming Dynasty (1,368–1,644 AD). Here we report eleven ancient genomes from four Hanging Coffin sites in China, alongside thirty whole genomes from the extant Bo people in Southwest China. We also sequence four ancient genomes from Log Coffin sites in northwestern Thailand. Our findings indicate that present-day Bo people derive a substantial proportion of their ancestry from practitioners of the Hanging Coffin mortuary tradition. Both ancient and modern groups exhibit elevated genetic affinity with coastal Neolithic populations from southern East Asia, who are ancestral to Tai-Kadai and Austronesian speakers. Unexpectedly, we also find evidence of long-range interactions and cultural inclusivity between Northeast Asian and Yellow River farmers and Hanging Coffin communities over 1,200 years ago. Finally, shared genetic components between Hanging (Log) Coffin populations in China and Thailand point to a common origin and a broader genetic and cultural network underlying this distinctive mortuary tradition across southern China and Southeast Asia.

In order to improve the hardness of the copper surface, reduce its friction coefficient, and adjust the overall performance of the coating, a TiB2/Cu composite coating with multilayer structure was prepared by electrodeposition. The microstructure of the composite coating was analyzed by SEM and XRD. The microhardness and friction characteristics of the coating were tested, and the differences in the microstructures and properties of different coating structures were analyzed. Microstructure coatings with two layers (Cu + TiB2/Cu) and three layers (Cu + TiB2/Cu + Cu) were prepared on the copper substrate by electrodeposition. The TiB2 particles reduced the deposition rate of the TiB2/Cu composite coating by electrodeposition, by up to 29%. The TiB2 particles in the electrolyte increased the discharge voltage of the electrodeposition process. The content of TiB2 affected the microhardness, friction, and wear properties of the TiB2/Cu composite coating. The TiB2 particles increased the microhardness of the TiB2/Cu composite coating by 61%. The multilayer-structured coating prepared by electrodeposition could control the overall properties of the coating. The microhardness and friction coefficient of the TiB2/Cu + Cu coating were between those of the Cu and TiB2/Cu composite coatings.

Painted stone carvings from Pujiang Museum in Chengdu were excavated from the Ming tombs near to Chengdu Metro Line 7. The Ming burial sites were the eunuch graves of the Shu King, and their tomb was constructed mostly of stone and decorated with paintings and carvings on its surface, which are of great value. However, during their burial, these painted stone carvings suffered significant salt damage. In this research, we performed optical microscope (OM) analysis, Raman spectra (RAM), ion chromatography (IC) analysis, X-ray fluorescence spectroscopy (XRF), X-ray powder diffraction (XRD), and petrographic microscopy (PM) to clarify the salt composition and influence. According to the results, the majority of the salt on the painted layer is CaSO4·2H2O. Before excavation, interaction between acid rain, soil, and groundwater created salt efflorescence on the paint layer’s surface. The deterioration of the paint layer caused by gypsum was divided into two stages: before excavation and during in situ preservation. This research provides a foundation for the removal and prevention of salt efflorescence.

Abstract The extinct Camelus knoblochi is known as the largest camel in genus Camelus, but its relationship to modern Camelus species remains unclear. In this study, we reported the first mitochondrial and nuclear analyses of seven Late Pleistocene C. knoblochi samples from Northeastern China. We found that they are inseparable to wild Bactrian camel on the matrilineal side, but belong to a distinct cluster on the biparental nuclear side. Further admixture proportion analyses suggested hybrid ancestry between both the ancestors of the modern wild and domesticated Bactrian camels, with ~65% contribution from the former and ~35% from the later. By calculating the coalescence time for three Camelus species above, we estimated the hybridization event occurred between approximately 0.8 and 0.33 Ma. We also used Bayesian skyline to reconstruct the maternal demographic trajectories for different Camelus to better compare their evolutionary histories. Our results provide molecular insights into C. knoblochi and fill in a vital piece in understanding the genus Camelus.

Through several years seedling-growing experiments in nursery in Daxing’an Mountains forest region, the author posed that the seedling cultivated for the region must possess the characteristics of being suited to thin and meager soil and having strong resistance to adverse conditions. For this purpose, the cultivation regime ought to be directization, standardization and programmatization; seedling growth ought to be promoted by regulating ecological conditions; and the mursery stock quality ought to be tested using vigor index.