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For cooperation and assistance in the work reported here, we gratefully acknowledge Dr. William Burgoyne, State of Alaska Division of Environmental Conservation and Mr. Delon Brown, USDA, Alaska Crop and Livestock Reporting Service. We especially appreciate the efforts of numerous pesticide manufacturers, distributors, dealers, and users who took the necessary time to provide information essential for this compilation. Richard Maxwell, Agricultural Chemicals Specialist, Cooperative Extension Service, Washington State University, provided difficult to locate pesticide label information. The editors of Farm Chemicals Handbook, 1980, provided the list of preferred names as well as information regarding general application of pesticide products.Acknowledgments -- Introduction -- Reference -- Pesticide Use in Alaska, 197

From the editors

Introduction to Volume 2, Issue 2 by the new Senior Student Editors

Distributional Impact of U.S. Farm Commodity Programs: Accounting for Alternative Farm Household Typologies

Agricultural households adjust to policy changes through market mechanisms by altering: their production mix, labor input, and on- and off-farm investments. Because of the significant heterogeneity among farms in the US agricultural sector, various types of farm households respond to the same policy change in significantly different ways. The parameters used to classify farm households into different typologies may also play a significant role in the interpretation of observed effects of policy changes. This paper, using a highly disaggregated U.S. Computable General Equilibrium (CGE) model, analyzes the distributional impacts of policy changes involving price-contingent government payments on alternative U.S. farm household typologies. We find that farm households do vary their responses to an elimination of price-contingent support based on location, production specialty, and farm categorization.Agricultural and Food Policy,

A trans10-18:1 enriched fraction from beef fed a barley grain-based diet induces lipogenic gene expression and reduces viability of HepG2 cells.

Beef fat is a natural source of trans (t) fatty acids, and is typically enriched with either t10-18:1 or t11-18:1. Little is known about the bioactivity of individual t-18:1 isomers, and the present study compared the effects of t9-18:1, cis (c)9-18:1 and trans (t)-18:1 fractions isolated from beef fat enriched with either t10-18:1 (HT10) or t11-18:1 (HT11). All 18:1 isomers resulted in reduced human liver (HepG2) cell viability relative to control. Both c9-18:1 and HT11were the least toxic, t9-18:1had dose response increased toxicity, and HT10 had the greatest toxicity (P<0.05). Incorporation of t18:1 isomers was 1.8-2.5 fold greater in triacylglycerol (TG) than phospholipids (PL), whereas Δ9 desaturation products were selectively incorporated into PL. Culturing HepG2 cells with t9-18:1 and HT10 increased (P<0.05) the Δ9 desaturation index (c9-16:1/16:0) compared to other fatty acid treatments. HT10 and t9-18:1 also increased expression of lipogenic genes (FAS, SCD1, HMGCR and SREBP2) compared to control (P<0.05), whereas c9-18:1 and HT11 did not affect the expression of these genes. Our results suggest effects of HT11 and c9-18:1 were similar to BSA control, whereas HT10 and t-9 18:1 (i.e. the predominant trans fatty acid isomer found in partially hydrogenated vegetable oils) were more cytotoxic and led to greater expression of lipogenic genes

A major QTL corresponding to the Rk locus for resistance to root-knot nematodes in cowpea (Vigna unguiculata L. Walp.).

Key messageGenome resolution of a major QTL associated with the Rk locus in cowpea for resistance to root-knot nematodes has significance for plant breeding programs and R gene characterization. Cowpea (Vigna unguiculata L. Walp.) is a susceptible host of root-knot nematodes (Meloidogyne spp.) (RKN), major plant-parasitic pests in global agriculture. To date, breeding for host resistance in cowpea has relied on phenotypic selection which requires time-consuming and expensive controlled infection assays. To facilitate marker-based selection, we aimed to identify and map quantitative trait loci (QTL) conferring the resistance trait. One recombinant inbred line (RIL) and two F2:3 populations, each derived from a cross between a susceptible and a resistant parent, were genotyped with genome-wide single nucleotide polymorphism (SNP) markers. The populations were screened in the field for root-galling symptoms and/or under growth-chamber conditions for nematode reproduction levels using M. incognita and M. javanica biotypes. One major QTL was mapped consistently on linkage group VuLG11 of each population. By genotyping additional cowpea lines and near-isogenic lines derived from conventional backcrossing, we confirmed that the detected QTL co-localized with the genome region associated with the Rk locus for RKN resistance that has been used in conventional breeding for many decades. This chromosomal location defined with flanking markers will be a valuable target in marker-assisted breeding and for positional cloning of genes controlling RKN resistance

Metallurgical Structures of As-Cast and Heat-Treated High-Palladium Dental Alloys

Scanning electron microscope observations and energy-dispersive spectroscopic analyses have been performed on two first-generation and two second-generation high-palladium dental casting alloys. A specimen design simulating a maxillary central incisor coping was employed to conserve metal, while providing thin and thick sections to yield a range of solidification rates. The alloys were centrifugally cast in air, following standard dental laboratory techniques; three castings were prepared for each alloy. Each casting was sectioned to produce two mirror-image specimens, and one specimen received the appropriate oxidation heat treatment, followed by a simulated full porcelain firing sequence. After metallographic polishing, specimens were examined with a scanning electron microscope. The as-cast alloys displayed multi-phase microstructures which could be explained by the rapid solidification conditions and the relevant phase diagrams. The simulated porcelain firing heat treatment caused a variety of bulk microstructural changes in the coping sections, along with formation of complex subsurface oxidation regions which were less thick for the second-generation alloys. Elemental compositions of the palladium solid solution matrix in the heat-treated alloys were in good agreement with nominal alloy compositions provided by the manufacturers. Ruthenium-rich particles found in the microstructures of three alloys are consistent with a proposed mechanism for grain refinement

Metallurgical Structures of As-Cast and Heat-Treated High-Palladium Dental Alloys

Scanning electron microscope observations and energy-dispersive spectroscopic analyses have been performed on two first-generation and two second-generation high-palladium dental casting alloys. A specimen design simulating a maxillary central incisor coping was employed to conserve metal, while providing thin and thick sections to yield a range of solidification rates. The alloys were centrifugally cast in air, following standard dental laboratory techniques; three castings were prepared for each alloy. Each casting was sectioned to produce two mirror-image specimens, and one specimen received the appropriate oxidation heat treatment, followed by a simulated full porcelain firing sequence. After metallographic polishing, specimens were examined with a scanning electron microscope. The as-cast alloys displayed multi-phase microstructures which could be explained by the rapid solidification conditions and the relevant phase diagrams. The simulated porcelain firing heat treatment caused a variety of bulk microstructural changes in the coping sections, along with formation of complex subsurface oxidation regions which were less thick for the second-generation alloys. Elemental compositions of the palladium solid solution matrix in the heat-treated alloys were in good agreement with nominal alloy compositions provided by the manufacturers. Ruthenium-rich particles found in the microstructures of three alloys are consistent with a proposed mechanism for grain refinement

X-Ray Diffraction and Scanning Electron Microscopy Analyses of a Gallium-Based Dental Restorative Alloy

Specimens of a gallium-based dental alloy were prepared with different condensation techniques, with and without the removal of a surface layer, and after aging for 2 hours at 50°, 100° and 150°C. X-ray diffraction at times ranging from 10 minutes to 1 day showed the development of the four matrix phases (ß-Sn, CuGa2, Ga28Ag72, and In4Ag9) during the setting reaction. Scanning electron microscope (SEM) examination of specimens loaded to failure revealed brittle fracture, with greater porosity for hand-condensed specimens, and provided insight into crack propagation processes. Aging increased the amount of ß-Sn in freshly prepared specimens, and removal of the Ga-rich surface layer after condensation decreased the amount of this phase. For specimens stored for 5 weeks at room temperature, aging substantially increased the amount of the CuGa2 phase but caused only moderate increases in the amount of ß-Sn