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A new species of the genus Gammarus Fabricius, 1775 is described and illustrated from Xinjiang Uygur Autonomous Region, China. Gammarus zhouqiongi sp. nov. is characterized by pereopods III--IV with long straight setae on posterior margins; inner ramus of uropod III more than twice as long as peduncle, reaching 0.7 times the length of outer ramus; inner ramus with plumose setae, and outer ramus with both plumose setae and long simple setae. Detailed morphological comparisons with related species are discussed. The K2P distances for each marker (CO1, 16S, 28S, and EF1α) of the new species differ from those of other Gammarus species in Xinjiang. Both phylogenetic trees based on separate (CO1, 16S, 28S, and EF1α) and combined (CO1+16S+28S+EF1α) markers show that the new species is an independent branch. A key to identify Gammarus species in Xinjiang is provided. [ABSTRACT FROM AUTHOR]

: In view of the unclear understanding of the basic scientific problems such as the rheological mechanism of seed cotton, especially the lack of research on the creep characteristics of seed cotton, the machine-harvested seed cotton in the Xinjiang region was taken as the research object to find out the compression creep characteristics. The universal material testing machine was used to carry out a one-factor creep test, taking moisture content, feed quality, compression times, and trash content as test factors and instantaneous elastic modulus, hysteretic elastic modulus, viscosity coefficient, and delay time as test indicators. The ANOVA and correlation were analyzed by SPSS, and the creep process of the seed cotton was simulated by ADAMS. Results show that moisture content significantly affects the instantaneous elastic modulus, hysteretic elastic modulus, and viscosity coefficient (p<0.01). In addition, each value of which decreases with the increase in moisture content. Feed quality significantly affects the hysteretic elastic modulus and viscosity coefficient (p<0.05). Moreover, the hysteretic elastic modulus and viscosity coefficient increase with the increase in feed quality. The compression times significantly influence the instantaneous elastic modulus, hysteretic elastic modulus, and viscosity coefficient (p<0.01), each value of which increases with the increase of compression times. Furthermore, the trash content significantly influenced the hysteretic elastic modulus and viscosity coefficient (p<0.05). The absolute error between the simulated and experimental values ek is within -0.011-0.030 mm, and the relative error φk is less than 7%. The experimental results can provide theoretical and data support for the study of rheological characteristics of machine-harvested seed cotton, the design of seed cotton packing devices, and the molding quality of cotton bale (mold). [ABSTRACT FROM AUTHOR]

Over the past decades, abundant and wellpreserved vertebrate fossils, known as the Urho Pterosaur Fauna, have been recovered from the Lower Cretaceous Tugulu Group in Junggar Basin, Xinjiang, NW China. Excavated materials belong to pterosaur, plesiosaur, dinosaur, crocodylomorph, and turtle taxa. As such, they provide key insights into the evolutionary history of several critical vertebrate groups in the Early Cretaceous. The Junggar assemblages have been interpreted as belonging to the Jehol Biota sensu lato, representing its northwesternmost known geographic extent. This research presents a new chemical abrasion--isotope dilution--thermal ionization mass spectrometry U-Pb age of 135.2 ± 0.9 Ma (2σ internal error) from a tuffaceous bed stratigraphically below the fauna-bearing layers, indicating a Valanginian maximum age for the Urho fauna. Combined with available biostratigraphic data, the results bear several important paleobiologic implications for the Early Cretaceous vertebrates. First, the Dsungaripterus pterosaur and Psittacosaurus ornithischian fauna appear to have emerged earlier than previously believed. Second, the data suggest that the oldest carcharodontosaurids in Asia appeared during the Valanginian Stage and extend the age range of basal coelurosaurs and basal crocodyliforms. Our results do not support the notion of the Jehol Biota sensu lato migrating as far west as the Junggar Basin in their later stages. The new information calls into question the temporal and spatial bases for the conventional, threestage evolutionary theory of the Jehol Biota. [ABSTRACT FROM AUTHOR]

In this study, we investigated Bartonella infection and its genetic diversity in rodents in Beitun, Xinjiang Uygur Autonomous Region, China. Small mammals were captured using snap traps at four sampling sites in 2018. Spleen and liver tissues were collected and cultured to isolate Bartonella strains. Whole-genome sequencing was performed on the strains identified as Bartonella by gltA gene PCR, and the average nucleotide identity (ANI) of the genomes was calculated by using FastANI v1.33. Phylogenetic trees were constructed for the samples positive for Bartonella spp. by the gltA PCR assay based on 1,290-bp gltA genes, 2,903-bp rpoB genes, and core-genome single nucleotide polymorphisms (SNPs). Among 66 rodents, 11 were positive for Bartonella, with an infection rate of 16.67%. The rodent infection rates in different tissues (χ² = 2.133; P = 0.242), species (χ² = 9.631; P = 0.141), and habitats (χ² = 4.309; P = 0.312) did not show statistical differences. Bartonella spp. isolated from the rodents were phylogenetically divided into six clades (two different Bartonella species were detected in two rodents). By comparing phylogenetic trees based on gltA genes, rpoB genes, and SNPs, we found that the topological structures of several evolutionary trees are different. However, the Bartonella strains isolated in this study were clustered into six clusters in different phylogenetic trees. Broad distributions and high genetic diversity of Bartonella strains were observed among rodents in Beitun, Xinjiang. IMPORTANCE: Rodent-borne Bartonella species have been associated with zoonotic diseases. Bartonella species such as Bartonella elizabethae, Bartonella grahamii, and Bartonella tribocorum can cause disease in humans. Humans can be infected by blood-sucking arthropods through the scratches and bites of an infected reservoir host or via contact with infectious rodents. Xinjiang is one of the provinces with the most abundant species of Bartonella in China, but there are few reports about the prevalence of Bartonella in the Beitun area. This research aims to investigate the occurrence and prevalence of Bartonella infection in rodents at these sampling sites and provide a basis for the prevention and control of rodent Bartonella species in Beitun and the surrounding areas of Xinjiang. [ABSTRACT FROM AUTHOR]