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Sablefish, Anoplopoma fimbria (also called black cod), is a long‐lived marine species with wide distribution extending from Baja California to Alaska, the Bering Sea, and through to the eastern coast of Japan. The landed weight of sablefish in the U.S. commercial fisheries is not large compared with other species; however, the exceptional value of sablefish has ranked it high compared with other species such as pollock, sockeye salmon, and Pacific cod. Sablefish are high in omega‐3 fatty acids and have white firm flesh with superior quality and taste. Current population levels are lower relative to historic ones and harvests have decreased within the last decade. The exceptional value of sablefish and decreases in wild populations have stimulated the development of methods to commercially aquaculture this species. Over the last 20 years, significant progress has been made in addressing the production of sablefish, and while there is still research that needs to be completed, sablefish have been commercially aquacultured by a small number of Canadian companies. In the Pacific Northwest, it is relatively easy to collect sablefish broodstocks from the wild and to transition them to land‐based rearing facilities. However, they must be maintained at cold temperatures to successfully reproduce. Captive broodstocks for genetic selection are not commercially available, though producers have begun their own development. Incubation conditions for yolk‐sac larvae have been developed and currently require long incubation periods at low temperatures, elevated salinity, and light exclusion. Although incubation times are long, they do not require very much attention during this phase. Exogenously feeding larvae currently require a regimen of rotifers and Artemia prior to dry feed habituation. However, tank characteristics, water turbidity, temperature, and illumination, as well as live feed enrichments have been studied. With the research that has been accomplished so far, survival rates of 10–40% have been routinely obtained at the larval stage. Despite a scarcity of species‐specific nutritional studies, researchers have shown that sablefish can be successfully cultured from the juvenile to the adult stage on commercial salmon feeds. Off‐the‐shelf salmon feeds have been used successfully in net‐pen grow‐out trials and are used by commercial producers. In addition, sablefish have proven to be a good cold‐water marine model for alternative feeds research. Still, research is needed to optimize nutritional requirements for all life stages of sablefish, develop practical feeds with these nutrient profiles, optimize feeding schedules, and produce life‐stage specific diets since the growth of sablefish differs according to size—most likely reflective of their complex life history. Sexually dimorphic growth in sablefish occurs during the typical grow‐out period, affecting time to harvest, the proportion of undersized (male) fish, and thus overall economic return to the producer. Production of all‐female monosex offspring at semi‐commercial scale using F‐1 progeny of neomales (XX males) generated through dietary treatment with 17α‐methyltestosterone is now possible. Results of long‐term feeding trials suggest that time to harvest at 2.5 kg from stocking at 75 g may be reduced by almost 3 months when monosex stocks are used. Econometric models reveal that internal rates of return are 11–15% higher for monosex relative to mix‐sex stocks over a 10‐year period under typical cage culture conditions. Sablefish are susceptible to diseases (furunculosis and vibriosis) brought on by atypical Aeromonas salmonicida and Vibrio anguillarum. Vaccination of sablefish using commercial vaccines to A. salmonicida (typical and atypical) has demonstrated that fish can be protected against a subsequent challenge by A. salmonicida, but this has only been effective by injection of the vaccine (not immersion) and how long the protection lasts has not been studied. More research is required to develop more effective vaccines, methods for vaccine delivery, and to understand conditions (ontogenetic and environmental) that may promote or enhance pathogenesis. [ABSTRACT FROM AUTHOR]

To quantify the efficacy and cost of different soya protein ingredients, heated soya beans (HSB) and underprocessed (SB) full‐fat soya beans (FFSB), soya protein concentrate (SPC) and trim waste from Pacific whiting (Merluccius productus) were incorporated into feeds for the cold water marine sablefish (Anoplopoma fimbria). Feed ingredients for this study were processed using an experimental heated ball mill with demonstrated potential as an affordable process for rural or small‐scale feed production. The three feed treatments were formulated with equal amounts of soya protein and Pacific whiting process trim. The three feed treatments contained 46% protein and 18% lipid as dry matter. Three 480‐L tanks of 10 fish were used to evaluate each of the three feed treatments. Fish were fed to satiation every 2 days for 8 weeks. Weight gain of the treatment groups ranged between 56% and 105% over the course of the study. Fish growth was significantly better among fish receiving the feeds containing HSB and SPC than a feed containing SB. At the conclusion of the study, histomorphologic evaluations of the distal intestines of final fish were conducted. Varying levels of inflammation were measured for all three treatments. Fisher's exact test showed a significant reduction in mononuclear cell infiltration among fish fed heat‐treated full‐fat soya beans vs those receiving underprocessed full‐fat soya beans. Fish receiving HSB feed had significantly lower intestinal inflammation than SB fish. Based on our results, cost savings of $ 0.253/kg were calculated for the HSB feed over the SPC feed. [ABSTRACT FROM AUTHOR]

Research indicated that informal interaction among principals in an urban school district took place through verbal means in dyads and triads rather than in larger groups, and suggested patterns of upward mobility from teaching to the principalship. Findings were compared with results of a similar study in a suburban district. (Author/MJL)

As global urban population increases and large cities densify, building departments and developers worldwide are looking to the structural engineering profession to develop ideas that allow vertical construction above transportation infrastructure and maximize the use of valuable real estate in the hearts of city centers. One Manhattan West (1MW) is a supertall building recently designed and engineered by Skidmore, Owings and Merrill (SOM). The tower rises above the underground train tracks approaching Pennsylvania Station in midtown Manhattan, New York City. The structural system of the tower consists of a central reinforced concrete core and a perimeter steel moment frame. The proximity of the train tracks prevents the perimeter columns of the 70-story building from coming down vertically and be directly supported on foundations. The primary challenge to the design team was to convert this limitation into an opportunity creating a column-free lobby at the base of a 304-m tall tower. Sloping back of the perimeter columns to the central core at the base not only addresses this challenge, it also gives 1MW the unique distinction as one of the slenderest structures in New York City. Innovative structural engineering design coupled with "out-of-the-box" project delivery method, developed and implemented by SOM, has made 1MW a reality. [ABSTRACT FROM AUTHOR]

Coho salmon Oncorhynchus kisutch are semelparous spawners with highly synchronized oocyte growth. Plasma was collected from maturing female fish and plasma lipids were quantified by lipoprotein class. Stable 13C isotopes were employed to investigate the origins of plasma lipids. Plasma lipoproteins were partitioned into the very low density ( VLDL), low density ( LDL), high density ( HDL) and very high density ( VHDL) lipoprotein classes. Lipids from all lipoprotein classes increased between the lipid droplet and early vitellogenesis stages of oocyte growth and VHDL lipids continued to increase through mid vitellogenesis ( P < 0.05). During vitellogenesis, total plasma lipid concentrations were similar to the sum of lipoprotein lipids ( P = 0.51). Plasma vitellogenin determined by an ELISA method was very well correlated with VHDL lipid during vitellogenesis ( R 2 = 0.91, n = 15). In general, the δ13C values of plasma lipids reflected that of feed (exogenous) and muscle (endogenous) lipids when feed and muscle δ13C values were similar, and were intermediate when differences existed between the two lipid sources. With one exception, the δ13C values of lipids from all lipoprotein classes within a plasma sample were similar. Results indicate that during sexual maturity, lipids from all plasma lipoprotein classes originate from a common pool of exogenous and endogenous lipids. [ABSTRACT FROM AUTHOR]

This article reports that gluten, the protein component of wheat, is toxic for patients with coeliac disease. Ingestion of gluten is associated with small intestinal damage, malabsorption of nutrients and elevated serum and intestinal antibodies against these cereal antigens. The development and duration of systemic tolerance to ingested gluten were examined by manipulating the diets of the mice at various stages in their growth. These results demonstrate that the ingestion of dietary gluten renders mice hyporesponsive to parenteral immunisation with gliadin.