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PubMed1990

The role of individualized care in a service delivery system for children and adolescents with severely maladjusted behavior.

Individualized care is a total system of care that is tailored to a child with severely maladjusted behavior. The services are unconditional, flexible, child and family focused, and interagency coordinated. The services follow the child until the child is adjusting in a normalized, mainstream environment. Individualized care is illustrated through two different projects. One is the Alaska Youth Initiative where individualized care was used to return children from out-of-state, residential programs. The other is Project Wraparound where it was used to prevent children from being removed from their families. This paper begins with the principles of individualized care and then describes the ecological, multilevel assessment process that coincides with the delivery of services. A case example from Project Wraparound is provided for clarification. Following the case example is a discussion of the need for evaluation data with some suggested strategies for documenting effectiveness. The final section focuses on two barriers to the implementation of individualized care. One is the tendency to think in terms of component programs rather than individualized services. The other barrier is the competition for scarce resources. Strategies are presented for overcoming both barriers.

Adolescent↗
PubMed2004

Subfreezing growth of the sea ice bacterium "Psychromonas ingrahamii".

"Psychromonas ingrahamii," named for John L. Ingraham, was isolated from sea ice from off Point Barrow, Alaska. This large rod-shaped bacterium belongs to the gamma-Proteobacteria. "P. ingrahamii" is a psychrophilic, heterotrophic bacterium that is gas vacuolate and nonmotile. "P. ingrahamii" is notable in that it grows at a temperature of -12 degrees C with a generation time of 240 h. This is the lowest growth temperature of any organism authenticated by a growth curve.

Alaska↗
PubMed2003

The tribal environment: solid waste in Indian country.

The issue of solid waste management in Indian country is multidimensional in scope because it affects more than just regulatory concerns. There are more than 550 federally recognized Alaska Native and American Indian Tribes in the United States. Tribes are sovereign nations that have a special relationship to the federal government and a unique legal status. The environmental problems faced by tribes are many, and it is only fair that tribes, as sovereigns, specify the levels of protection on their lands. The one-size-fits-all regulatory approach to environmental problems and solid waste management in particular does not work and often leads to conflict between tribes and the federal and state governments. Inherent tensions also exist between tribes and various levels of government concerning jurisdiction of lands and managing solid waste. These intergovernmental relationships are often complex and present unique challenges to all. More research needs to be done on targeting resources to meet the capacity-building needs of tribes, as well as the overall environmental management needs of Indian country under the federal trust obligation. Successful intergovernmental relationships can be fostered through partnership arrangements between tribes and federal, state, and local governments. In the area of solid waste such partnerships have worked. It requires that all levels of government deal with tribes with careful consideration of their cultural, historic, and socioeconomic aspects, which are often intertwined.

Alaska↗
PubMed2003

Feedback dynamics of grazing lawns: coupling vegetation change with animal growth.

We studied the effects of grazing by Black Brant (Branta bernicla nigricans) geese (hereafter Brant) on plant community zonation and gosling growth between 1987 and 2000 at a nesting colony in southwestern Alaska. The preferred forage of Brant, Carex subspathacea, is only found as a grazing lawn. An alternate forage species, C. ramenskii, exists primarily as meadow but also forms grazing lawns when heavily grazed. We mowed plots of ungrazed C. ramenskii meadows to create swards that Brant could select and maintain as grazing lawns. Fecal counts were higher on mowed plots than on control plots in the year after plots were mowed. Both nutritional quality and aboveground biomass of C. ramenskii in mowed plots were similar to that of C. subspathacea grazing lawns. The areal extent of grazing lawns depends in part on the population size of Brant. High Brant populations can increase the areal extent of grazing lawns, which favors the growth of goslings. Grazing lawns increased from 3% to 8% of surface area as the areal extent of C. ramenskii meadows declined between 1991 and 1999. Gosling mass was lower early in this time period due to density dependent effects. As the goose population stabilized, and area of grazing lawns increased, gosling mass increased between 1993 and 1999. Because larger goslings have increased survival, higher probability of breeding, and higher fecundity, herbivore-mediated changes in the distribution grazing lawn extent may result in a numerical increase of the population within the next two decades.

Alaska↗
PubMed2003

Consumption of salmon by Alaskan brown bears: a trade-off between nutritional requirements and the risk of infanticide?

The risk of infanticide may alter foraging decisions made by females, which otherwise would have been based on nutritional requirements and forage quality and availability. In systems where meat resources are spatially aggregated in late summer and fall, female brown bears (Ursus arctos) would be faced with a trade-off situation. The need of reproductive females to accumulate adequate fat stores would likely result in a decision to frequent salmon streams and consume the protein- and lipid-rich spawning salmon. In contrast, aggregations of bears along salmon streams would create conditions of high risk of infanticide. We investigated consumption of salmon by brown bears on Admiralty and Chichagof Islands in Southeast Alaska from 1982 to 2000 using stable isotope analysis and radiotelemetry. While nearly all males (22 of 23) consumed relatively large amounts of salmon (i.e., >10% relative contribution to seasonal diet), not all females (n=56) did so. Five of 26 females for which we had reproductive data, occupied home ranges that had no access to salmon and thus did not consume salmon when they were mated or accompanied by young. Of females that had access to salmon streams (n=21), all mated individuals (n=16) had delta(15)N values indicative of salmon consumption. In contrast, 4 out of 16 females with cubs avoided consuming salmon altogether, and of the other 12, 3 consumed less salmon than they did when they were mated. For 11 of 21 females with access to salmon streams we had data encompassing both reproductive states. Five of those altered foraging strategies and exhibited significantly lower values of delta(15)N when accompanied by young than when mated, while 6 did not. Radiotelemetry data indicated that females with spring cubs were found, on average, further away from streams during the spawning season compared with females with no young, but both did not differ from males and females with yearlings and 2-year-olds. Females with young that avoided salmon streams were significantly lighter indicating that female choice to avoid consumption of salmon carries a cost that may translate to lower female or cub survivorship. The role of the social hierarchy of males and females, mating history, and paternity in affecting the risk of infanticide and foraging decisions of female brown bears merit further investigation.

Adipose Tissue↗
PubMed2004

Tight coupling between leaf area index and foliage N content in arctic plant communities.

The large spatial heterogeneity of arctic landscapes complicates efforts to quantify key processes of these ecosystems, for example productivity, at the landscape level. Robust relationships that help to simplify and explain observed patterns, are thus powerful tools for understanding and predicting vegetation distribution and dynamics. Here we present the same linear relationship between Leaf area index (LAI) and Total foliar nitrogen (TFN), the two factors determining the photosynthetic capacity of vegetation, across a wide range of tundra vegetation types in both northern Sweden and Alaska between leaf area indices of 0 and 1 m2 m(-2), which is essentially the entire range of leaf area index values for the Arctic as a whole. Surprisingly, this simple relationship arises as an emergent property at the plant community level, whereas at the species level a large variability in leaf traits exists. As the relationship between LAI and TFN exists among such varied ecosystems, the arctic environment must impose tight constraints on vegetation canopy development. This relationship simplifies the quantification of vegetation productivity of arctic vegetation types as the two most important drivers of productivity can be estimated reliably from remotely sensed NDVI images.

Alaska↗
PubMed2004

Warming chambers stimulate early season growth of an arctic sedge: results of a minirhizotron field study.

We examined the effects of passive open-top warming chambers on Eriophorum vaginatum production near Toolik Lake, Alaska, USA. During the 2002 growing season, chamber warming was consistent with the magnitude and seasonality observed in recent decades throughout northwestern North America. Leaf-growth rates were higher in late May and early June; maximum growth rates in each leaf cohort occurred earlier and peak biomass was observed 20 days earlier within the chambers. Consequently, plants within the chambers maintained more live leaf biomass during the period of highest photosynthetically active radiation. Annual leaf production within the chambers (21+/-2 mg tiller) was not significantly different than under ambient conditions (17+/-2 mg tiller) (P=0.2256) despite higher early-season growth rates. Root growth began earlier; growth rates were higher in late May and early June, and maximum growth rates occurred earlier within the chambers. Therefore, plants within the chambers maintained greater root biomass during what earlier studies have identified as a period of relatively high nutrient availability. Annual root production within the chambers (191+/-42 g m-2) was not significantly different than under ambient conditions (119+/-48 g m-2) (P=0.1979), although there was a trend toward higher production within the chambers. The tendency toward higher root production within the chambers is consistent with previous laboratory experiments and with the predictions of biomass allocation theory.

Alaska↗
PubMed2005

Inter-annual variability of NDVI in response to long-term warming and fertilization in wet sedge and tussock tundra.

This study explores the relationship between the normalized difference vegetation index (NDVI) and aboveground plant biomass for tussock tundra vegetation and compares it to a previously established NDVI-biomass relationship for wet sedge tundra vegetation. In addition, we explore inter-annual variation in NDVI in both these contrasting vegetation communities. All measurements were taken across long-term experimental treatments in wet sedge and tussock tundra communities at the Toolik Lake Long Term Ecological Research (LTER) site, in northern Alaska. Over 15 years (for wet sedge tundra) and 14 years (for tussock tundra), N and P were applied in factorial experiments (N, P and N+P), air temperature was increased using greenhouses with and without N+P fertilizer, and light intensity was reduced by 50% using shade cloth. during the peak growing seasons of 2001, 2002, and 2003, NDVI measurements were made in both the wet sedge and tussock tundra experimental treatment plots, creating a 3-year time series of inter-annual variation in NDVI. We found that: (1) across all tussock experimental tundra treatments, NDVI is correlated with aboveground plant biomass (r2 = 0.59); (2) NDVI-biomass relationships for tussock and wet sedge tundra communities are community specific, and; (3) NDVI values for tussock tundra communities are typically, but not always, greater than for wet sedge tundra communities across all experimental treatments. We suggest that differences between the response of wet sedge and tussock tundra communities in the same experimental treatments result from the contrasting degree of heterogeneity in species and functional types that characterize each of these Arctic tundra vegetation communities.

Alaska↗
PubMed2006

Successional and physical controls on the retention of nitrogen in an undisturbed boreal forest ecosystem.

Floristic succession in the boreal forest can have a dramatic influence on ecosystem nutrient cycling. We predicted that a decrease in plant and microbial demand for nitrogen (N) during the transition from mid- to late-succession forests would induce an increase in the leaching of dissolved inorganic nitrogen (DIN), relative to dissolved organic nitrogen (DON). To test this, we examined the chemistry of the soil solution collected from within and below the main rooting zones of mid- and late-succession forests, located along the Tanana River in interior Alaska. We also used a combination of hydrological and chemical analyses to investigate a key assumption of our methodology: that patterns of soil water movement did not change during this transition. Between stands, there was no difference in the proportion of DIN below the rooting zone. 84-98% of DIN at both depths consisted of nitrate, which was significantly higher in the deeper mineral soil than at the soil surface (0.46+/-0.12 mg NO(-) (3) -N l(-1) vs 0.17+/-0.12 mg NO(-) (3) -N l(-1), respectively), and 79-92% of the total dissolved N consisted of DON. Contrary to our original assumption that nutrients were primarily leached downward, out of the rooting zone, we found much evidence to suggest that the glacially-fed Tanana River (>200 m from these stands) was contributing to the influx of water and nutrients into the soil active layer of both stands. Soil water potentials were positively correlated with river discharge; and ionic and isotopic (delta(18)O of H(2)O) values of the soil solution closely matched those of river water. Thus, our ability to elucidate biological control over ecosystem N retention was confounded by riverine nutrient inputs. Climatic warming is likely to extend the season of glacial melt and increase riverine nutrient inputs to forests along glacially-fed rivers.

Alaska↗
PubMed2005

Annoying vacation souvenir: Fish tapeworm (Diphyllobothrium sp.) infestation in an Austrian fisherman.

Diphyllobothriosis is infestation with the fish tapeworm. Although the worldwide incidence has decreased in recent decades, increased travel and the new popularity of dishes involving raw fish (e.g. sushi) may provide a higher risk of infestation in formerly low-risk areas. We report an Austrian fisherman who passed a 75 cm tapeworm segment in his stool. Infestation presumably occurred 14 months earlier during a fishing tour in Alaska. At presentation, the patient was asymptomatic, reported no weight loss and showed neither anaemia nor eosinophilia. He was cured with a single dose of 10 mg/kg body weight praziquantel.

Alaska↗
PubMed2003

Determination of genetic sex in chinook salmon (Oncorhynchus tshawytscha) using the male-linked growth hormone pseudogene by real-time PCR.

This study used a real-time quantitative polymerase chain reaction (qPCR) method based on the growth hormone pseudogene (GHp) in chinook salmon (Oncorhynchus tshawytscha) to determine genetic sex. The GHp is present as a single copy in the genome of the male chinook salmon but is absent in the female, providing a means of using this real-time qPCR method to discriminate genetic sex. Comparisons between genomic DNA samples from 2 geographically distinct populations of chinook salmon (Columbia River, Washington, and Yukon River, Alaska) showed, within each population examined, that the males were clearly differentiated from the females. There were no interpopulation differences between males or females. The advantages of this real-time qPCR method are that it is rapid, is amenable to high sample throughput, and provides an accurate numerical value that allows comparisons between samples by statistical methods.

Alaska↗
PubMedDate not supplied

Assignment of sockeye salmon (Oncorhynchus nerka) to spawning sites using DNA markers.

Randomly amplified polymorphic DNA (RAPD) markers were used to assign individual adult sockeye salmon to their spawning sites using a genotype assignment test. Six primers were selected for use by screening bulked DNA samples for markers missing in fish from one or more of 5 sites in British Columbia or Alaska. Of 73 markers scored, 54 showed variation between or within sites among the sampled fish. Thirty-seven of the variable markers were not detected in any fish from one or more sites; 18 variable markers were detected in all fish from one or more other sites. Thus 25% of markers scored were found in all fish of some sites and in no fish of some other sites. An assignment test placed all 70 fish tested into their correct populations. Principal coordinate analysis of genetic variation produced clusters of fish corresponding to each sampling site. No sex-specific RAPD markers were detected among more than 1300 screened.

Alaska↗
PubMed2005

Population structure and stock identification of Eulachon (Thaleichthys pacificus), an anadromous smelt, in the pacific northwest.

The genetic structure of eulachon (Thaleichthys pacificus) populations was examined in an analysis of variation of 14 microsatellite loci representing approximately 1900 fish from 9 sites between the Columbia River and Cook Inlet, Alaska. Significant genetic differentiation occurred among the putative populations. The mean F(ST) for all loci was 0.0046, and there was a significant correlation between population genetic differentiation (F(ST)) and geographic distance. Simulated mixed-stock samples comprising populations from different regions suggested that variation at microsatellite loci provided reasonably accurate estimates of stock composition for potential fishery samples. Marine sampling indicated that immature eulachons from different rivers, during the 2 to 3 years of prespawning life in offshore marine waters, do not mix thoroughly. For eulachons captured incidentally in offshore trawl fisheries, there was a clear geographic cline in relative abundance of eulachons from different geographic areas. The sample from northern British Columbia was dominated by northern and central coastal populations of British Columbia, the sample from central British Columbia was composed of eulachons from all regions, and the sample from southern British Columbia was dominated by Columbia River and Fraser River populations. These results have implications for the management of trawl fisheries and conservation of spawning populations in some rivers where abundance is at historically low levels.

Alaska↗
PubMed2006

Selecting species for marine assessment of radionuclides around Amchitka: planning for diverse goals and interests.

Considerable attention has been devoted to selecting bioindicator species as part of monitoring programs for exposure and effects from contaminants in the environment. Yet the rationale for selection of bioindicators is often literature-based, rather than developed with a firm site-specific base of data on contaminant levels in a diverse range of organisms at different trophic levels in the same ecosystem. We suggest that this latter step is an important phase in the environmental assessment process that is often missing. In this paper we address the problem of how to select a wide range of species representing different trophic levels that serve as a basis for selecting a few species suitable as bioindicators. We illustrate this with our assessment of radionuclides on Amchitka Island, Alaska. We propose a multi-stage process for arriving at the list of available species that includes review of literature, review by experts experienced in the area, review by interested and affected parties, selection of trophic levels or groups for analysis, arraying of possible species, and selection of species within each trophic level group for sample collection. We first had to identify all likely species, then narrow our focus to those we could collect and analyze. In all cases, review includes suggestions for possible target species with justifications. While this method increases the up-front costs of developing bioindicators for an ecosystem, it has the advantage of providing information for selection of species that will be most informative in the long run, including those that are the best bioaccumulators, thus providing the earliest warning of any potential environmental consequences. Further, the recognition that a range of stakeholder's needs and interests should be included increases the utility for public-policy makers, and the potential for continued usage to establish long-term trends.

Alaska↗
PubMed1985

Superficial and systemic illness related to a hot tub.

In an outbreak of folliculitis in Alaska among bathers in a contaminated hot tub, one person was found in whom follicular lesions were preceded by deep, tender, peripheral nodules. Of nine affected bathers, five showed inflammation of Montgomery's follicles of the breast. Bathing longer in the tub and later in the day was associated with increased risk of disease. This investigation added serotype O-7,8 to the list of pseudomonads associated with hot tub infections.

Adult↗
PubMed1993

Current activities within the National Biomonitoring Specimen Bank.

The National Institute of Standards and Technology (NIST) has been involved in biological environmental specimen banking activities since 1979. These activities, which are known collectively as the National Biomonitoring Specimen Bank (NBSB), include the banking of a variety of specimens (human liver, sediment, mussels/oysters, fish tissue and marine mammal tissues) from several different projects supported by different government agencies. The two most recent projects, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) and the National Marine Mammal Tissue Bank (NMMTB), focus on the collection, banking and analysis of marine mammal tissues and they are part of a comprehensive plan to address marine mammal monitoring, specimen banking and quality assurance of analytical measurements associated with contaminant analyses in marine mammals.

Alaska↗
PubMed1993

Determination of PCBs and chlorinated hydrocarbons in marine mammal tissues.

Selected tissues (blubber, liver, kidney and muscle) from marine mammals, which were collected as part of the Alaska Marine Mammal Tissue Archival Project (AMMTAP), were analyzed for polychlorinated biphenyl (PCB) congeners and chlorinated pesticides. Concentrations of these compounds in the different tissues were compared and blubber was selected as the primary tissue for organic contaminant analyses for the AMMTAP based on higher levels (1-2 orders of magnitude) in this tissue compared to liver, kidney and muscle. Concentrations for 15 PCB congeners and 12 chlorinated pesticides are reported for 10 different animals of three species (northern fur seal, ringed seal and belukha whale) from five different sites.

Adipose Tissue↗
PubMed1993

Determination of inorganic constituents in marine mammal tissues.

Analyses of selected tissues from the Alaska Marine Mammal Tissue Archival Project (AMMTAP) have provided comprehensive information related to levels of 36 trace elements and methyl-mercury in marine mammal tissues. Liver, kidney and muscle tissues from two northern fur seals, four ringed seals and six belukha whales were analyzed. The bulk of the investigated tissues and additional tissues from a total of 65 marine mammals are banked in the AMMTAP. The results are compared to literature values for trace element concentrations in marine mammal tissues and their relevance to environmental studies is discussed.

Alaska↗