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During 2009, the Alaska Division of Geological & Geophysical Surveys continued a program, begun in 2006, of reconnaissance mapping of surficial geology in the proposed natural-gas pipeline corridor through the upper Tanana River valley. The study area is a 12-mi-wide (19.3-km-wide) area that straddles the Alaska Highway from the western boundaries of the Tanacross B-3 and A-3 quadrangles near Tetlin Junction eastward to the eastern boundaries of the Nabesna D-1 and C-1 quadrangles along the Canada border. Mapping during 2008-2009 in the Tanacross and Nabesna quadrangles linked with the mapping completed in the Tanacross, Big Delta and Mt. Hayes quadrangles in 2006-2008. Surficial geology was initially mapped in this third corridor segment by interpreting ~1:65,000-scale, false-color, infrared aerial photographs taken in July 1978 and August 1981 and plotting unit boundaries on acetate overlays. Verification of photo mapping was accomplished during the 2008 and 2009 summer field seasons, when map units were described, soil pits were hand dug, and samples were collected for analyses. The engineering-geologic map is derived electronically from the surficial-geologic map and shows the distribution of surficial-geologic and bedrock units grouped genetically with common properties that are typically significant for engineering applications.

During 2009, the Alaska Division of Geological & Geophysical Surveys continued a program, begun in 2006, of reconnaissance mapping of surficial geology in the proposed natural-gas pipeline corridor through the upper Tanana River valley. The study area is a 12-mi-wide (19.3-km-wide) area that straddles the Alaska Highway from the western boundaries of the Tanacross B-3 and A-3 quadrangles near Tetlin Junction eastward to the eastern boundaries of the Nabesna D-1 and C-1 quadrangles along the Canada border. Mapping during 2008-2009 in the Tanacross and Nabesna quadrangles linked with the mapping completed in the Tanacross, Big Delta and Mt. Hayes quadrangles in 2006-2008. Surficial geology was initially mapped in this third corridor segment by interpreting ~1:65,000-scale, false-color, infrared aerial photographs taken in July 1978 and August 1981 and plotting unit boundaries on acetate overlays. Verification of photo mapping was accomplished during the 2008 and 2009 summer field seasons, when map units were described, soil pits were hand dug, and samples were collected for analyses.

During 2009 the Alaska Division of Geological & Geophysical Surveys (DGGS) conducted reconnaissance interpretive mapping of permafrost in Alaska Highway Corridor Segment 3, a 12-mi-wide (19.3-km-wide) corridor that straddles the Alaska Highway through the Northway-Tanacross Lowland and the southern Yukon-Tanana Upland from Tetlin Junction to the Canada border. This work was an extension of permafrost mapping done in Alaska Highway Corridor Segment 1 from Delta Junction to Dot Lake in the Big Delta and Mt. Hayes Quadrangles during 2006-2007 and Alaska Highway Corridor Segment 2 from the Robertson River to Tetlin Junction in the Tanacross Quadrangles during 2008. Primarily, we inferred the extent of permafrost and ice content by interpreting ~1:65,000-scale, false-color infrared aerial photographs taken in July 1978 and August 1981.

Mineral-resources personnel from the Alaska Division of Geological & Geophysical Surveys conducted reconnaissance sampling of the William Henry Bay area in the Juneau C-4 and D-4 quadrangles, August 9-13, 2011. This sampling project was part of a statewide assessment of Alaska's potential for rare-earth element mineralization. During the William Henry Bay field project 46 rock, sediment, and heavy-mineral concentrate samples were collected for geochemical analysis (geochemical, major oxide, minor oxide, trace element, and rare earth elements).

Northern-blot hybridization, also referred to as Northern blotting, is one of several methods developed to detect the presence, to determine the size, and to quantify specific cellular mRNAs. By this method, total RNA or poly(A)(+)mRNA, prepared from the cells or tissue of interest, is fractionated by size on a denaturing agarose gel. The separated RNAs are transferred to a membrane by capillary action or under a vacuum and hybridized to a labeled probe with a base sequence complementary to all or part of the target mRNA. Analysis of hybridization signals determines whether the gene of interest is expressed in the cells or tissue, as well as the size and relative quantity of the target mRNA, if appropriate markers are used.

An accumulating body of evidence strongly indicates a local tissue renin-angiotensin system in the pancreas of a various species. In contrast to the majority of tissues that primarily express the angiotensin type 1 (AT1) receptor, the pancreas is one of the few tissues that contain a significant proportion of the AT2 subtype. Moreover, our findings indicate a greater distribution angiotensin II binding sites in the exocrine pancreas. Although the physiological aspects of a local pancreatic renin-angiotensin system remain largely unexplored, recent studies in our laboratory utilizing an acinar cell model demonstrate both functional AT1 and AT2 receptors. Indeed, we show that the AR42J cell line expresses all components of an angiotensin system including the mRNA for renin, angiotensinogen, angiotensin converting enzyme (ACE), AT1a, AT1b and AT2 receptors. Thus, these cells may be of particular value to study the interplay of the AT1 and AT2 receptors to regulate cell growth and potentially exocrine function.

We previously described a protein, isolated from human tissues and cells, that bound to a defined double-stranded oligonucleotide containing a single site-specifically placed 1,N6-ethenoadenine. It was further demonstrated that this protein was a glycosylase and released 1,N6-ethenoadenine. We now find that this enzyme also releases 3-methyladenine from methylated DNA and that 3-methyladenine-DNA glycosylase behaves in the same manner, binding to the ethenoadenine-containing oligonucleotide and cleaving both ethenoadenine and 3-methyladenine from DNA containing these adducts. The rate and extent of glycosylase activities toward the two adducts are similar.

Prolactin receptors have been identified in estrone-progesterone induced mammary tumors from GR mice. 125I-labeled ovine prolactin binding to tumor homogenates reached a steady state in 12 hours at 22 degrees and was specific for prolactin. Prolactin receptors were highest (16 fmoles/mg protein) in primary, hormone-dependent tumors and declined progressively in transplanted hormone-dependent and transplanted hormone-responsive tumors. In autonomous tumors, binding was approximately 5% of that found in primary tumors. Scatchard analysis of binding to selected tumors indicated that the observed decrease in bound hormone was due to a loss in the number of receptor sites; binding affinity was unaltered (kd approximately 1 X 10(-10) M). Since receptors for estrogen and progesterone as well as those for prolactin decline in a concerted manner with the transition to autonomy, autonomous growth may result from a loss of receptors or an increase in the relative proportion of autonomous cells present in the tumor.

The UV-irradiated, 3'-end-labeled, 92-base-pair terminus of the human alphoid sequence was incubated with purified endonuclease v. Previously unreported photoproducts were incised at purine loci. These were not pyrimidine photodimers, 6-4'-(pyrimidin-2'-one)-pyrimidines, base loss sites, or ring-opened purines. Therefore, purine-containing photoproducts, possibly dimers, were incised by the enzyme preparation.