Virulence and Infectivity of UC,MD, and L Strains of Infectious Hematopoietic Necrosis Virus (IHNV) in Four Populations of Columbia River Basin Chinook Salmon

Infectious Hematopoietic Necrosis Virus (IHNV) infects juvenile salmonid fish in conservation hatcheries and aquaculture facilities, and in some cases, causes lethal disease. This study assesses intra-specific variation in the IHNV susceptibility of Chinook salmon (Oncorhynchus tshawytscha) in the Columbia River Basin (CRB), in the northwestern United States. The virulence and infectivity of IHNV strains from three divergent virus genogroups are measured in four Chinook salmon populations, including spring-run and fall-run fish from the lower or upper regions of the CRB. Following controlled laboratory exposures, our results show that the positive control L strain had significantly higher virulence, and the UC and MD strains that predominate in the CRB had equivalently low virulence, consistent with field observations. By several experimental measures, there was little variation in host susceptibility to infection or disease. However, a small number of exceptions suggested that the lower CRB spring-run Chinook salmon population may be less susceptible than other populations tested. The UC and MD viruses did not differ in infectivity, indicating that the observed asymmetric field prevalence in which IHNV detected in CRB Chinook salmon is 83% UC and 17% MD is not due to the UC virus being more infectious. Overall, we report little intra-species variation in CRB Chinook salmon susceptibility to UC or MD IHNV infection or disease, and suggest that other factors may instead influence the ecology of IHNV in the CRB.     

吐鲁番盆地世界人群常见慢性病流行病学调查

目的探讨吐鲁番盆地不同海拔地区长期居住人群的常见慢性病的流行病学调查及其生理特征。 方法对在吐鲁番盆地长期居住人群按不同不同海拔地区分为海拔0米区（设为0米组）、海平面以下50米区（设为-50米组）、海平面以下100米区（设为-100米组）及海平面以下150米区（设为-150米组）等4组。采用便携式氧饱和度议测定血氧饱和度（SaO₂）,瑞特血糖仪测定指尖血糖（FPG）,全自动生化分析仪测定甘油三酯（TG）、总胆固醇（TC）、高密度脂蛋白-胆固醇（HDL-C）、低密度脂蛋白-胆固醇（LDL-C）、血尿酸（UA）、尿素氮（BUN）和肌酐（Cr）来查明不同海拔高度、不同氧分压环境下维吾尔族和汉族人群的SaO₂及相同海拔高度、氧分压环境下维吾尔族与汉族人群生理生化特征的比较。 结果相同海拔高度、相同氧分压环境下,维吾尔族和汉族人群的血氧饱和度水平比较,差异无统计学意义（P＞0.05）;0米和海平面以下50米海拔高度、氧分压环境下维吾尔族与汉族人群UA水平比较,差异有统计学意义（P＜0.05）;海平面以下150米海拔高度、氧分压环境下维吾尔族与汉族人群TG、TC水平以及胃食管反流病（GERD）典型症状（烧心、反流及睡眠障碍）评分之间比较,差异有统计学意义（P＜0.05）;随着海拔高度的增高维吾尔族与汉族人群TG、TC水平呈增高趋势。 结论不同海拔高度、不同氧分压情况下环境因素对人群血氧饱和度、血脂及GERD症状的发生有一定的影响,需要在该地区人群中加强宣传健康教育,进行合理的饮食指导,积极预防地域相关心血管疾病及 GERD 的发生和发展。     

塔里木盆地啮齿动物体外寄生蚤群落的研究

目的掌握塔里木盆地啮齿动物体外寄生蚤的群落组成和结构。方法根据地理区划和生境类型选择调查点,按样方法捕获啮齿动物,对体外寄生蚤进行单独鉴定,采用群落生态学技术方法,计算各鼠类蚤类群落的组成和结构。结果在塔里木盆地共捕获啮齿动物7种351只,获体外寄生蚤10种683只,构建7个鼠类蚤类群落。结论子午沙鼠体外寄生蚤的蚤指数、丰富度和多样性3项指标均较高,对该地区蚤类群落的构成和稳定起到了积极的作用,长耳跳鼠和三趾跳鼠的蚤类群落结构相似,并与子午沙鼠蚤类群落形成结构上的互补性,对维持塔里木盆地蚤类群落构亦具有重要的作用;群落间的相似性比较分析表明,塔里木盆地的7个鼠类蚤类群落归为跳鼠蚤类群落、家栖或半家栖鼠类蚤类群落和子午沙鼠蚤类群落3个类群。     

From the Cover: Anthropogenic lead pervasive in Canadian Arctic seawater

Anthropogenic Pb is widespread in the environment including remote places. However, its presence in Canadian Arctic seawater is thought to be negligible based on low dissolved Pb (dPb) concentrations and proxy data. Here, we measured dPb isotopes in Arctic seawater with very low dPb concentrations (average ∼5 pmol ⋅ kg⁻¹) and show that anthropogenic Pb is pervasive and often dominant in the western Arctic Ocean. Pb isotopes further reveal that historic aerosol Pb from Europe and Russia (Eurasia) deposited to the Arctic during the 20th century, and subsequently remobilized, is a significant source of dPb, particularly in water layers with relatively higher dPb concentrations (up to 16 pmol ⋅ kg⁻¹). The 20th century Eurasian Pb is present predominantly in the upper 1,000 m near the shelf but is also detected in older deep water (2,000 to 2,500 m). These findings highlight the importance of the remobilization of anthropogenic Pb associated with previously deposited aerosols, especially those that were emitted during the peak of Pb emissions in the 20th century. This remobilization might be further enhanced because of accelerated melting of permafrost and ice along with increased coastal erosion in the Arctic. Additionally, the detection of 20th century Eurasian Pb in deep water helps constrain ventilation ages. Overall, this study shows that Pb isotopes in Arctic seawater are useful as a gauge of changing particulate and contaminant sources, such as those resulting from increased remobilization (e.g., coastal erosion) and potentially also those associated with increased human activities (e.g., mining and shipping).

Human activities have significantly altered the geochemical cycle of Pb with anthropogenic sources (e.g., leaded gasoline in the 20th century, coal combustion, and smelting) overwhelming natural sources (e.g., crustal particles and volcanic eruptions) (1–3). Anthropogenic Pb is also far reaching because Pb emissions from high-temperature processes can attach, nucleate, and condense to fine aerosol particles, allowing its dispersion over vast distances and deposition in remote places (4, 5). In the ocean, aerosol Pb can enter the water column through a variety of pathways and is redistributed laterally and vertically via ocean circulation. Biogenic (e.g., plankton and organic matter) and authigenic particles also influence the distribution by scavenging the dissolved Pb (dPb), with the estimated dPb residence time in surface waters rich with these particles being shorter (<1 y) (6) than in the deep water (∼100 y) (7, 8) with fewer particles.Although the Arctic is very remote, anthropogenic Pb from the midlatitude regions reaches the Arctic via atmospheric transport, as evidenced in aerosols (9, 10), snow (11, 12), and ice cores (11, 13, 14). This influx is particularly high during the Arctic haze period (winter and spring) when pollution from Europe and Russia (Eurasia) reaches the Arctic atmosphere (15). Anthropogenic Pb from aerosols can become incorporated in the Arctic Ocean through wet and dry deposition of aerosols (16), resuspension from coasts and shelves, river input, and sea ice melting. However, to date, the atmospheric pathway, which is dominated by anthropogenic Pb (1), is not considered a major source of dPb to the western Arctic Ocean (refer to Fig. 1A for the Arctic map). Based on a few proxy measurements from Arctic lake sediments (17), abyssal sediments (18), and Fe–Mn crusts (19) in the western Arctic, major contributions of anthropogenic Pb were not found, and therefore, the contribution of dPb from atmospheric deposition was not considered to be a major source. Abyssal sediments and Fe–Mn crusts in the ocean along with lake sediments are used as proxies to assess the presence of dPb in the water column, because Pb is particle reactive and is readily incorporated in these materials (18, 20). In particular, a study (18) on Pb in abyssal sediments in the Arctic Ocean found evidence of anthropogenic Pb in the abyssal sediments of the eastern but not the western Arctic Ocean. The authors attributed this difference to how Pb is scavenged from Atlantic waters entering the Arctic Ocean. Waters reaching the western Arctic Ocean mainly pass through the highly productive and particle-rich Barents Sea, allowing dPb to be largely scavenged, while waters reaching the eastern Arctic Ocean pass through the Fram Strait and undergo less scavenging (18). With what is assumed to be a limited contribution from anthropogenic Pb, it is thought that dPb in the western Arctic seawater would likely be predominantly natural Pb from coastal and riverine inputs. However, to date, no study has clearly assessed the relative importance of anthropogenic and natural Pb sources directly in Arctic Ocean seawater.Open in a separate windowFig. 1.Maps of the Arctic and the sampling stations (CB1 to CB4 and CAA8). (A) The study area (red ellipse) and relevant geographic features in the Arctic based on Rudels (60). The Arctic Ocean has four basins separated by submarine ridges (red text). The CB and Makarov Basin (MB) make up the Western Arctic Ocean, and the Amundsen Basin (AB) and Nansen Basin (NB) make up the Eastern Arctic Ocean. The Pacific-derived water (PW, green arrow) enters Bering Strait (BeS), goes to the CB and MB, and makes up the upper halocline layer. The Atlantic-derived water (AW, blue arrows) enters Fram Strait (FS), and Barents Sea (BaS) travels along the shelves and slopes and reaches all the basins. In the CB, the AW makes up the lower halocline layer, Atlantic water layer, and deep water. The PW from the CB goes to the Canadian Arctic Archipelago (CAA), Baffin Bay (BB), Labrador Sea (LS), and eventually the Atlantic Ocean. (B) The sampling locations in the CB are stations CAA8 and CB1 to CB4.The 2015 Canadian Arctic Geotraces Cruise (GN03) provided an opportunity to measure both dPb and Pb isotopes in seawater samples from the Canada Basin (CB, a part of the western Arctic Ocean; Fig. 1A). The dPb data (21) showed extraordinarily low dPb concentrations in the CB, with higher levels of dPb observed in the Pacific-derived water layer, suggesting that some of this dPb came from the Pacific inflow. However, given the very low-Pb concentrations, it was hard to determine the provenance of this Pb from concentrations alone. Thus, we present here Pb isotopes from the same samples (CB1 to CB4 and CAA8 stations collectively referred to as CB; Fig. 1B) in order to assess the different sources of Pb in the water column.Our results show that anthropogenic Pb is pervasive in the Arctic, even at water column depths with low dPb concentrations. We also identified 20th century Eurasian Pb, which is present in different water layers and at depths with relatively higher dPb, as an important component of the dPb. This 20th century Eurasian Pb has a distinctively low ²⁰⁶Pb/²⁰⁷Pb ratios, offering insights into the pathway and distribution of anthropogenic Pb in the water column. Our results indicate that remobilization of previously deposited aerosols, especially from the high-Pb emission period (e.g., peak of leaded gasoline in the 20th century), contributes significantly to the dPb budget of the CB.     

塔里木板块晚奥陶世牙形石属Taoqupognathus An的分布及对比

塔里木板块见Taoqupognathus An 的两个种:Taoqupognathus blandus An和 T. tumidus Trotter & Webby. T. blandus An的出现层位、共生牙形石分子与鄂尔多斯盆地大致相同,始于Belodina compressa与Periodon grandis组合,上延至Yaoxianognathus yaoxianensis带,广泛分布于塔里木库鲁克塔格地区乌里格孜塔格剖面乌里格孜塔格组和轮南、英买力、塔中等20余口钻井剖面良里塔格组;T. tumidus见于轮南、英买力、塔中少数钻井剖面良里塔格组上部至桑塔木组Yaoxianognathus yaoxianensis带。在中国T. blandus的始现层位比澳大利亚低,消失层位比澳大利亚更高;T. tumidus存在层位与澳大利亚大致相当。     

Capoeta damascina (Valenciennes, 1842), a new host of Contracaecum sp. and Capillaria sp. (Nematoda) from the Kor River Basin,southwestern Iran

ObjectiveTo investigate the parasitic infection status of cyprinid fish, Capoeta damascina in Gomban spring-stream, Kor River Basin, Fars Province, southwestern Iran.MethodsA total of 12 cyprinid fish (7 females and 5 males) were collected from Gomban spring-stream, Kor River Basin, Fars Province, southwestern Iran. The collected fish were dissected carefully and their internal organs such as liver, gonad, muscle, abdominal lobes, whole viscera and digestive tract were surveyed parasitologically.ResultsOne female cyprinid fish out of 12 fish was infected with three nematodes. Two nematodes (larvae) were identified as Contracaecum sp. which were attached firmly to the outer part of intestine and another adult helminth was recognized as Capillaria sp. which was recovered from digestive content.ConclusionsThis study is the first record indicating that cyprinid fish acts as a new host for recovered nematodes. Further helminthological investigations are highly recommended in different parts of Iran in order to expand our knowledge about helmintic parasites of cyprinid fish and their role in transmission of diseases to human and animal.     

塔里木盆地三种扇头蜱的鉴别要点

目的 澄清三种扇头蜱的存在,列出3种扇头蜱的鉴别要点.方法 从不同自然景观和家、野生动物体上采集蜱类进行分类鉴定.结果 共获得蜱类18 000余只.经鉴定隶属2科5属10种.结论 其中优势蜱种为璃眼蜱属Hyalomma中的种类.其次是扇头蜱属Rhipicephalus、革蜱属Dermacentor、血蜱属Haemaphysalis和钝缘蜱属Ornithodoros的种类.     

OVT域叠前裂缝预测技术研究应用

以塔里木盆地中古地区全方位高密度地震资料为基础,采用叠前纵波方位各向异性技术开展OVT域裂缝预测研究。OVT域地震数据较常规数据能量更为均衡,信噪比更高,且偏移后保留了方位角和偏移距信息,能快速灵活进行方位角和偏移距分选,避免了常规方法耗时长的弊端,适合进行分方位裂缝预测。通过对该地区奥陶系鹰山组石灰岩储层不同偏移距、不同方位角及不同域的数据体进行试验,优选出100~5500m偏移距和6个方位角的数据来计算纵波相对波阻抗的差异,裂缝方向和密度的预测结果与实钻吻合程度较高,能够为该井区储层缝洞连通性研究、井位部署、水平井井轨迹设计提供重要依据。     

塔里木油田潜油电泵管柱失效分析及应对措施

通过对塔里木油田潜油电泵管柱失效井的统计、分析,认为油管腐蚀穿孔、油管丝扣冲蚀、电潜泵和分离器外壳腐蚀穿孔或断裂、电泵机组连接螺栓断裂,是造成电泵管柱失效的主要原因。现场实践表明:通过改进电泵井下井工具防腐性能,优化管柱设计,严格执行电泵井井下作业相关操作标准,提高现场作业人员的操作技能,可以提高电泵井完井质量,延长潜油电泵管柱有效期,减少因管柱失效造成的检泵、检管作业,对提高塔里木电泵井管理水平具有现实意义。