Understanding drivers of mercury in lake trout (Salvelinus namaycush), a top-predator fish in southwest Alaska's parklands.

Mercury (Hg) is a widespread element and persistent pollutant, harmful to fish, wildlife, and humans in its organic, methylated form. The risk of Hg contamination is driven by factors that regulate Hg loading, methylation, bioaccumulation, and biomagnification. In remote locations, with infrequent access and limited data, understanding the relative importance of these factors can pose a challenge.

Intervention initiatives to raise young people's interest and participation in STEM.

For nearly a decade, two science interventions anchored in project-based learning (PBL) principles have been shown to increase student science learning in 3 grade and high school physical science classes. Both interventions employed a randomized control trial of several thousand students (N = 3,271 in 3 grade and N = 4,238 in 10, 11, and 12 grades). Incorporating a rich background of research studies and reports, the two interventions are based on the ideas of PBL as well as the National Academies of Science's publications, including how children learn; how science learning and instruction can be transformed; and the performance expectations for science learning articulated in the Next Generation of Science Standards.

Using carbon, nitrogen, and mercury isotope values to distinguish mercury sources to Alaskan lake trout.

Lake trout (), collected from 13 remote lakes located in southwestern Alaska, were analyzed for carbon, nitrogen, and mercury (Hg) stable isotope values to assess the importance of migrating oceanic salmon, volcanic activity, and atmospheric deposition to fish Hg burden. Methylmercury (MeHg) bioaccumulation in phytoplankton (5.0 - 6.

U.S. and Finnish high school science engagement during the COVID-19 pandemic.

When the COVID-19 pandemic struck, research teams in the United States and Finland were collaborating on a study to improve adolescent academic engagement in chemistry and physics and the impact remote teaching on academic, social, and emotional learning. The ongoing "Crafting Engaging Science Environments" (CESE) intervention afforded a rare data collection opportunity. In the United States, students were surveyed at the beginning of the school year and again in May, providing information for the same 751 students from before and during the pandemic.

Nest use dynamics of an undisturbed population of bald eagles.

Management or conservation targets based on demographic rates should be evaluated within the context of expected population dynamics of the species of interest. Wild populations can experience stable, cyclical, or complex dynamics, therefore undisturbed populations can provide background needed to evaluate programmatic success. Many raptor species have recovered from large declines caused by environmental contaminants, making them strong candidates for ongoing efforts to understand population dynamics and ecosystem processes in response to human-caused stressors.

A practitioner's guide for exploring water quality patterns using principal components analysis and Procrustes.

To design sustainable water quality monitoring programs, practitioners must choose meaningful variables, justify the temporal and spatial extent of measurements, and demonstrate that program objectives are successfully achieved after implementation. Consequently, data must be analyzed across several variables and often from multiple sites and seasons. Multivariate techniques such as ordination are common throughout the water quality literature, but methods vary widely and could benefit from greater standardization.

Trends in developed land cover adjacent to habitat for threatened salmon in Puget Sound, Washington, USA.

For widely distributed species at risk, such as Pacific salmon (Oncorhynchus spp.), habitat monitoring is both essential and challenging. Only recently have widespread monitoring programs been implemented for salmon habitat in the Pacific Northwest.

Interactive effects of water diversion and climate change for juvenile chinook salmon in the lemhi river basin (USA.).

The combined effects of water diversion and climate change are a major conservation challenge for freshwater ecosystems. In the Lemhi Basin, Idaho (U.S.

Big dams and salmon evolution: changes in thermal regimes and their potential evolutionary consequences.

Dams designed for hydropower and other purposes alter the environments of many economically important fishes, including Chinook salmon (Oncorhynchus tshawytscha). We estimated that dams on the Rogue River, the Willamette River, the Cowlitz River, and Fall Creek decreased water temperatures during summer and increased water temperatures during fall and winter. These thermal changes undoubtedly impact the behavior, physiology, and life histories of Chinook salmon.

Quantitative threat analysis for management of an imperiled species: Chinook salmon (Oncorhynchus tshawytscha).

Chinook salmon (Oncorhynchus tshawytscha) have declined dramatically across the Pacific Northwest because of multiple human impacts colloquially characterized as the four "H's": habitat degradation, harvest, hydroelectric and other dams, and hatchery production. We use this conceptual framework to quantify the relative importance of major threats to the current status of 201 Chinook populations. Current status is characterized by two demographic indices: population density and trend.

Projected impacts of climate change on salmon habitat restoration.

Throughout the world, efforts are under way to restore watersheds, but restoration planning rarely accounts for future climate change. Using a series of linked models of climate, land cover, hydrology, and salmon population dynamics, we investigated the impacts of climate change on the effectiveness of proposed habitat restoration efforts designed to recover depleted Chinook salmon populations in a Pacific Northwest river basin. Model results indicate a large negative impact of climate change on freshwater salmon habitat.

Wilms tumor suppressor, Wt1, is a transcriptional activator of the erythropoietin gene.

Molecular mechanisms for the developmental stage and tissue-specific regulation of the erythropoietin (EPO) gene are poorly understood. Recent findings indicate a role of the Wilms tumor suppressor, Wt1, in the formation of the hematopoietic system. Herein, we tested the hypothesis that Wt1 is a transcriptional regulator of the EPO gene.

The orientation experiences of urgent care nurses: sources of learning.

The purpose of this qualitative study was to characterize and explain the unique features relating to the orientation of newly hired nurses in an urgent care setting. The learning needs of professionally experienced nurses are examined as nurses change their context of work. The methodology for this study was exploratory, using descriptive and evaluative case studies.

Lymphocytic colitis, induced by ticlopidine.

Lymphocytic colitis is a chronic inflammatory colonic disease characterized by watery diarrhea and a dense infiltration of the colonic mucosa with lymphocytes. The etiology is unknown but an immune reaction to various immunostimulatory agents including pathogenic or commensal bacteria, products of bacterial metabolism of dietary degradation, or antigens derived directly from the diet, and autoimmune phenomena are discussed. We observed a patient with all features of lymphocytic colitis characterized by a prominent intraepithelial T-cell component.

[Campylobacter pylori and gastritis--the density of colonization and degree of inflammation. A semiquantitative and morphometric study].

Gastric biopsies of 1000 patients were grouped according to their diagnoses, special interest was devoted to type B-gastritis. Density of Campylobacter pylori colonization was determined semiquantitatively after Warthin-Starry silver impregnation. Bacteria could never be seen in normal mucosa.

[The course and treatment of an ovarian pregnancy in the 3d trimester].

The course of a right ovarian pregnancy advanced up to the 35th week is described. The only pathognomonical symptom was a constant retrocervical tumor which was not identified as the contracted uterus. The analysis of this and 16 further cases of such ovarian pregnancies published between 1950 and 1981 leeds to the following conclusions: 1.

[Classical low back pain and sciatica syndrome caused by a melanotic nerv sheath tumour of the first sacral root (author's transl)].

This is the description of the case of a 22 year old patient with low back pain and sciatica on the right side investigated by lumbar Dimer-X-Myelography. The result of the examination was an impression in the contrast column at the L5/S 1 level on the right. At operation an intradural tumour, plum-sized, well-defined, and blue-black in colour, was found and removed.