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891.
892.
New replacement names are proposed for seven species of the subfamily Typhlocybinae; one new synonym is recognized in the family Delphacidae. The following changes are proposed: Empoasca (Empoasca) angustata nom.nov. for Empoasca angusta Linnavuori & DeLong (not Dworakowska); Empoasca (Empoasca) chilensis nom.nov. for Empoasca diversa Linnavuori & DeLong (not Vilbaste); Austroasca verdensis nom.nov. for Empoasca artemisiae Lindberg (not Lethierry); Kropka vidanoi Dworakowska for Erythroneura unipunctata Dlabola (not Cerutti); Zyginella vietnamica nom. nov. for Zyginella melichari Dworakowska (not Kirkaldy); Eupteryx (Eupteryx) dlabolai nom. nov. for Eupteryx octonotata Dlabola (not Hardy); Baaora ahmedi nom. nov. for Baaora spinosa (Ahmed) (not Beamer); Paradelphacodes insolitus Dmitriev is synonymized with Paradelphacodes gvosdevi (Mitjaev), syn. nov.  相似文献   
893.
Students of ethnic identity have recently begun to recognize the role of the state in causing identity shift. Constructivists, in particular, focus on the importance of state institutions and policies in creating new identities and transforming old ones. This article focuses on identity creation and change in Bashkortostan, an ethnic region within the Russian Federation. It shows how, at the beginning of the twentieth century, the Russian/Soviet state created new ethnic identities from pre-existing regional, estate-based and religious identities. It also shows how later changes in state institutions and policies played a crucial role in determining the direction of identity change among a mixed population, straddling the geographical and cultural boundaries between the Tatar and Bashkir ethnic groups. By tracing the impact of the state on one ethnic group over an extended time-period, this article shows that state actions can lead to both instrumental and culturally-based shifts in ethnic identity.  相似文献   
894.
895.
New geological data from Lake Ladoga are presented and an interpretation of the Late Pleistocene and Holocene history of the lake is given. The deglaciation of the southern part of the lake and an origin of the first ice margin Lake Ladoga took place at ca. 14,000 yr B.P.  相似文献   
896.
We discovered a structurally novel SCD (Δ9 desaturase) inhibitor 4a (CVT-11,563) that has 119 nM potency in a human cell-based (HEPG2) SCD assay and selectivity against Δ5 and Δ6 desaturases. This compound has 90% oral bioavailability (rat) and excellent plasma exposure (dAUC 935 ng h/mL). Additionally, 4a shows moderately selective liver distribution (three times vs plasma and adipose tissue) and relatively low brain penetration. In a five-day study (high sucrose diet, rat) compound 4a significantly reduced SCD activity as determined by GC analysis of fatty acid composition in plasma and liver. We describe the discovery of 4a from HTS hit 1 followed by scaffold replacement and SAR studies focused on DMPK properties.  相似文献   
897.
898.
Several studies have shown that experienced night-migratory songbirds can determine their position, but it has remained a mystery which cues and sensory mechanisms they use, in particular, those used to determine longitude (east–west position). One potential solution would be to use a magnetic map or signpost mechanism like the one documented in sea turtles. Night-migratory songbirds have a magnetic compass in their eyes and a second magnetic sense with unknown biological function involving the ophthalmic branch of the trigeminal nerve (V1). Could V1 be involved in determining east–west position? We displaced 57 Eurasian reed warblers (Acrocephalus scirpaceus) with or without sectioned V1. Sham operated birds corrected their orientation towards the breeding area after displacement like the untreated controls did. In contrast, V1-sectioned birds did not correct for the displacement. They oriented in the same direction after the displacement as they had done at the capture site. Thus, an intact ophthalmic branch of the trigeminal nerve is necessary for detecting the 1,000 km eastward displacement in this night-migratory songbird. Our results suggest that V1 carries map-related information used in a large-scale map or signpost sense that the reed warblers needed to determine their approximate geographical position and/or an east–west coordinate.  相似文献   
899.
900.
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