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Objective: We aim to investigate the species composition of ticks and the pathogen characteristics they carry in the Argun port area of the China–Russia border. Materials and Methods: Ticks were collected in surrounding grassland, mixed forest land, and other different habitats around the Argun port area at the Sino-Russian Border of Inner Mongolia in China in April 2019. The presence of 16 potential pathogens, including Yersinia Pestis, Francisella tularensis, Coxiella burnetii (Cb), Anaplasma sp. (Ap), spotted fever group rickettsiae (SFG Rk), Borrelia sp. (Bl), Leptospira, Bartonella spp., Babesia, Crimean-Congo hemorrhagic fever virus, tick-borne encephalitis virus, Bhanja virus, West Nile Virus, severe fever with thrombocytopenia syndrome bunyavirus, Hantaan virus, and bocavirus (boca) was analyzed by polymerase chain reaction. The DNA and amino acid sequences of tick-borne pathogens were compared for homology, and the phylogenetic trees were constructed by using Mega and Lasergene software. Results: A total of 210 ticks were collected and they belonged to three species: Dermacentor nuttalli, Ixodes persulcatus, and Haemaphysalis verticalis. Among them, 165 (78.57%) ticks tested positive for 5 pathogens, namely Ap, SFG Rk, Cb, Bl, and boca. Fifteen (7.14%) ticks were detected coinfection with two pathogens, and none were coinfected with three or more pathogens. Conclusion: This study shows the prevalence of at least five tick-borne pathogens in Argun, and there is a risk of coinfection by two pathogens in one tick. This study reveals the great importance of controlling tick-borne diseases in this region. [ABSTRACT FROM AUTHOR]

Mukawa virus (MKWV), a novel tick-borne virus (TBV) of the genus Phlebovirus of family Phenuiviridae , has been firstly reported in Ixodes persulcatus in Japan. In this study, we made an epidemiological investigation in China to obtain the geographic distribution and genetic features of this virus outside Japan. We screened 1,815 adult ticks (665 I. persulcatus , 336 Dermacentor silvarum , 599 Haemaphysalis longicornis , 170 Rhipicephalus microplus , 45 Haemaphysalis concinna) and 805 wild small mammals collected from eight provinces. The positive rate of 6.77% (45/665, including 18 female and 27 male I. persulcatus) and 2.22% (1/45, 1 male H. concinna) were obtained from I. persulcatus and H. concinna in Heilongjiang province, respectively. No evidence of MKWV infection was found in other three tick species or any of the mammalian species. The virus can infect the Vero cells successfully, indicating the ability of MKWV to replicate in mammalian cells. A phylogenetic tree based on the nucleotide sequences of L, M, and S segments demonstrated that the Japanese MKWV variant, our two MKWV variants, and KURV were clustered with the members of the mosquito/sandfly-borne phleboviruses and distant from other tick-borne phenuiviruses. A phylogenetic analysis based on 895 bp partial L gene sequences (n = 46) showed that all MKWV sequences were separated into three lineages. Our results showed the presence of MKWV in I. persulcatus and H. concinna in northeast of China, highlighting the necessity of epidemiological study in wider regions. Due to the ability of MKWV to replicate in mammalian cells, the potential for zoonosis, and wide distribution of I. persulcatus and H. concinna in China, the important vectors of MKWV, further screening to more tick species, wild animals, domestic animals, and humans raises up practical significance. [ABSTRACT FROM AUTHOR]

The stability of maize production in Northeast China where rain-fed agriculture is widely practiced faces serious challenges due to climate change. Therefore, to investigate how the mechanisms of conservation tillage affect maize yield, a 4-y study (2018–2021) with two planting densities (60,000 and 90,000 plants ha−1) and three tillage treatments (CT: conventional tillage; RT: reduced tillage; NT: no tillage) was conducted in a 39-y, long-term field experiment. Under 60,000 plants ha−1, maize grain yield was 13.8% higher in NT and 19.6% higher in RT than in CT, whereas under 90,000 plants ha−1, yields were 10.6% higher in NT and 12.6% higher in RT. Reduced and no tillage increased yields compared with those in CT by increasing harvesting ears, kernels per ear, and 1,000-kernel weight. Compared with CT, long-term RT also increased the harvest index under both planting densities, whereas NT only increased the harvest index under 60,000 plants ha−1. Compared with CT, long-term RT and NT increased maize plant height, canopy radiation interception rate, and leaf photosynthetic physiology (i.e., photosynthetic rate, maximal quantum yield of photosystem II photochemistry and actual photochemical efficiency of photosystem II). However, radiation and temperature production efficiency were not different among tillage treatments at either plant density, an interesting target when further improving yield level and stability. Based on the results, RT and NT are recommended to be integrated into crop cultivation strategies for rain-fed agriculture in Northeast China, which is expected to mitigate the adverse effects of increased climatic challenges. [Display omitted] • Maize production is unstable due to frequent climatic challenges in Northeast China. • Reduced and no tillage increase yield stability in semi-arid rain-fed regions. • Reduced and no tillage are recommended for agriculture in Northeast China. • Improving radiation production efficiency is an interesting target for the conservation tillage. [ABSTRACT FROM AUTHOR]

In December 2019, a buffer tank burst accident occurred in the maintenance of liquefied natural gas (LNG) bus in China. Failure analysis revealed the bus‐mounted buffer tank had been subjected to an excessive internal pressurization, although the tank material met the specifications for engineering practice. The physical evidence related to the failed tank showed that a chemical explosion was impossible. As water was used to pouring the frozen pipeline prior to the accident, according to the consequences observed, the rapid phase transition (RPT) explosion of the residual LNG due to external heat from water was regarded as the main causation of incident. The explosion energy was inversely estimated by the TNT equivalent method, and the rapid expansion of natural gas produced excessive pressure, thus causing the buffer tank to explode. [ABSTRACT FROM AUTHOR]

Little is known about Epstein-Barr virus (EBV)-associated intrahepatic cholangiocarcinoma (EBVaICC) because of its rarity. We aimed to comprehensively investigate the clinicopathology, tumor immune microenvironment (TIME) and genomic landscape of this entity in southern China. We evaluated 303 intrahepatic cholangiocarcinomas (ICCs) using in situ hybridization for EBV. We compared clinicopathological parameters between EBVaICC and nonEBVaICC, and we analyzed EBV infection status, tumor-infiltrating lymphocytes (TILs) and genomic features of EBVaICC by immunohistochemistry, double staining, nested PCR, multiplex immunofluorescence staining, fluorescence in situ hybridization and whole-exome sequencing. EBVaICC accounted for 6.6% of ICCs and was associated with EBV latency type I infection and clonal EBV isolates. Patients with EBVaICC were more often female and younger, with solitary tumors, higher HBV infection rates and less frequent cirrhosis; the lymphoepithelioma-like (LEL) subtype was more common in EBVaICC. EBVaICC was associated with a significantly larger TIME component than nonEBVaICC. The LEL subtype of EBVaICC – associated with a significantly increased density and proportion of CD20+ B cells and CD8+ T cells – was associated with significantly higher 2-year survival rates than conventional EBVaICC and nonEBVaICC. Both PD-1 and PD-L1 in TILs, and PD-L1 in tumor cells, were overexpressed in EBVaICC. High PD-L1 expression in tumor cells and high CD8+ TIL densities were significantly more common in EBVaICC than in nonEBVaICC. Seven genes (MUC4 , DNAH1, GLI2 , LIPE , MYH7 , RP11-766F14.2 and WDR36) were mutated in at least 3 patients. EBVaICC had a different mutational pattern to liver fluke-associated cholangiocarcinoma and HBV-associated ICC. EBVaICC, as a subset of ICC, has unique etiological, clinicopathological and genetic characteristics, with a significantly larger TIME component. Paradoxically, patients with EBVaICC could be candidates for immune checkpoint therapy. Epstein-Barr virus (EBV) is associated with a subtype of intrahepatic cholangiocarcinoma, with unique clinicopathological and genetic characteristics. The tumor immune microenvironment is also different in this tumor subtype and patients with EBV-associated intrahepatic cholangiocarcinoma may respond well to immune checkpoint inhibitors. [Display omitted] • EBVaICC accounted for 6.6% of ICCs and was associated with EBV latency type I infection and clonal EBV isolates. • EBVaICChas unique characteristics related to etiology, clinicopathology and molecular genetics. • Both PD-1 and PD-L1 in tumor-infiltrating lymphocytes and PD-L1 in tumor cells are overexpressed in EBVaICC. • Patients with EBVaICC may respond well to immune checkpoint inhibitors. • The lymphoepithelioma-like subtype of EBVaICC is related to favorable survival. [ABSTRACT FROM AUTHOR]

We analyzed age structure and dynamics, spatial distribution patterns, and reproductive capabilities of four Rosa persica populations in Xinjiang, to evaluate the survival status of the species and explore the reasons behind its endangerment. The results showed that the populations had fewer individuals in the youngest (Ⅰ) and oldest (Ⅵ-Ⅷ) age classes, with a predominance of middle-aged individuals, resulting in an irregular pyramid-shaped distribution, described as "high in the middle, low on both sides". The populations were generally growing, but were susceptible to external environmental disturbances ( V pi ' ＞0, P max ＞0). The mortality rate ( q x ) and vanish rate ( K x ) peaked at age Ⅴ, leading to a sharp decline in plant abundance. The life expectancy ( e x ) decreased progressively with the increases of age class, reaching its lowest at age Ⅷ, which indicated minimal vitality at this stage. A time sequence analysis predicted a future dominance of individuals at age Ⅴ-Ⅷ, suggesting an aging trend. Spatially, the four populations were predominantly clumped, with the intensity of clumping ranked from highest to lowest as P 4 , P 3 , P 1 , and P 2 . P 3 and P 4 exhibited better reproductive capabilities than P 1 and P 2 . There was a significant positive correlation between hundred-fruit weight and plant height and crown width, and between total seed number and crown width and hundred-fruit weight.

Understanding climate change and extreme climate is of great significance for ensuring food security and socio-economic development of the Songhua River Basin. Based on the daily precipitation, maximum temperature and minimum temperature data during 1961-2020 from 69 meteorological stations in and around the Songhua River Basin, we analyzed the temporal and spatial variations of extreme temperature and precipitation in the Songhua River Basin using 27 extreme climate indices recommended by the World Meteorological Organization, and linear trend method, Mann-Kendall trend test and ordinary Kriging interpolation methodology. The results showed that, from 1961 to 2020, except for cold speel duration, the extreme cold index in the study area showed a downward trend, while the extreme warm index, extreme value index and other temperature indices showed an upward trend. The increasing trend of the minimum temperature was greater than that of the maximum temperature. Icing days, cold speel duration and warm speel duration showed an increasing trend from south to north, while the minimum value of maximum temperature and that of minimum temperature showed opposite spatial characteristics. The high value areas of summer days and tropical nights were mainly distributed in the southwestern region, while there was no obvious spatial variations of cool days, warm nights, and warm days. Overall, except for cold speel duration, other extreme cold indices had a rapid decreasing trend in the north and west of the Songhua River Basin. In the warm index, summer days, warm nights, warm days, and warm speel duration had a rapid upward trend in the north and west, and tropical nights had the fastest rise in the southwest. In the extreme value index, the maximum of temperature rose fastest in the northwest, while the minimum rose fastest in the northeast. Except for consecutive dry days, the rest of precipitation indices showed an increasing trend, and the fastest rising areas were mainly in the north-central part of the Nenjiang River Basin, while some areas in the south of the Nenjiang River Basin became dry. Heavy precipitation days, very heavy precipitation days, heaviest precipitation days, consecutive wet days, very wet day precipitation, extremely wet day precipitation, and annual precipitation showed a gradual decreasing pattern from southeast to northwest. Overall, the Songhua River Basin was warming and wetting, but there were some differences among different regions, especially the northern and southern parts of the Nenjiang River Basin.

To gain more insights into epidemiologic characteristics and genotype of hantavirus in Apodemus agrarius in Changbai Area. Complete hantavirus S segment sequences were amplified by RT-PCR and sequenced. The phylogenetic trees were constructed for analysis of genetic characters of hantavirus. A total of 58 Apodemus agrarius were trapped in the epidemic areas, and complete hantavirus S segment sequences were obtained from 4 lung samples of these rodents (6. 90%0). Phylogenetic analysis of the four S segment sequences indicated that all viruses isolated from Apodemu sagrarius were closely related to genotype 6 of Hantaan virus (95. 8%-96. 3%, nucleotide identity; 98. 6%-99. 5%, amino acid identity), all of them had a specific S387 different from other genotypes of Hantaan virus.

Amur virus was recently identified as the causative agent of hemorrhagic fever with renal syndrome. Here we report the complete genome sequence of an Amur virus isolated from Apodemus peninsulae in Northeastern China. The sequence information provided here is critical for the molecular epidemiology and evolution of Amur virus in China.

Characteristics of heavy metal distributions in surface sediments of different areas in the Yellow River Delta coastal wetland are analyzed, and the influences of sediment environment on heavy metal distributions are discussed. Heavy metal pollution and potential ecological risk in surface sediments of the Yellow River Delta coastal wetland are estimated by using Hakanson potential ecological risk (PER) factors method. The analyzed results indicate that the average contents of Hg, Cu, Pb, Zn, Cd and Cr are 0.034, 18.733, 19.393, 65.317, 0.235 and 62.940 microg x g(-1), respectively. The heavy metal distributions vary with regional environment changes. The accumulating index of heavy metals in the current outfall area is the highest of the three regions assigned by author,the second is that of the ancient Yellow River Delta in the north of Shandong province, and the lowest is that of the abandoned delta. Heavy metal distributions in the Yellow River Delta coastal wetland are affected significantly by hydrodynamic system. In addition, the content of clay in surface sediments plays an important role in the distribution and accumulation of heavy metals. The results also suggest that the heavy metal pollution in the Yellow River Delta coastal wetland is in a low pollution level, with a comprehensive pollution index varying from 0.10 to 4.14. And element Cr is the major pollution factor and its average of single pollution index is 0.63. The order of pollution extents of six typical pollutants is Cr > Cu > Zn > Cd > Pb > Hg. The comprehensive potential ecological risk index is between 0.46 and 51.88, indicating a low potential ecological risk. The order of potential ecological risk parameter is Cd > Hg > Cu > Cr > Pb > Zn. Element Cd is also the major factor of potential ecological risks in the Yellow River Delta coastal wetland.

The effectiveness of the attractants 1-octen-3-ol (octenol) and L-lactic acid (Lurex) on the collection of Aedes albopictus, Culex tritaeniorhynchus, Cx. pipiens pallens, and Anopheles sinensis was first evaluated in Mosquito Magnet Pro traps in Yamenkou and Badachu residential areas, Beijing City, and Lishui area, Zhejiang Province, China. The Mosquito Magnet Pro traps baited with octenol collected significantly more Ae. albopictus, Cx. tritaeniorhynchus, and An. sinensis, but fewer Cx. pipiens pallens than collection by the traps alone. There were no significant differences in the numbers of Cx. pipiens pallens, Cx. tritaeniorhynchus, and An. sinensis collected by Mosquito Magnet Pro traps baited with Lurex compared to the traps alone, but the Mosquito Magnet Pro traps baited with Lurex collected significantly more Ae. albopictus than the number collected by the traps alone at 2 areas in Beijing.

Objective: To isolate and identify Banna virus (BAV) from mosquitoes collected in Mengla county of Yunnan province., Methods: Mosquito samples were collected in houses and stock yards in Mengla county, 2008. Mosquitoes were homogenized and incubated onto both C6/36 and BHK21 cells. The new isolate was identified by using ELISA and RT-PCR. The sequences of segment 5, 8 and 11 of BAV were amplified by RT-PCR and determined. Phylogenetic analysis on the new BAV were performed using MEGA4 program., Results: 1731 mosquitoes representing 7 species were collected with one strain of BAV isolated and identified. Phylogenetic analysis based on sequences of segment 8 showed the new isolate was closed to BAV strain isolated in Yunnan, but segment 11 sequence was closed to Vietnam strain., Conclusion: Results of phylogenetic analysis implied that the BAV re-assortment might have been occurred both in Chinese and Vietnam strains.