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20th century climate warming and tree-limit rise in the southern Scandes of Sweden.

https://arctichealth.org/en/permalink/ahliterature95958
Source
Ambio. 2001 Mar;30(2):72-80
Publication Type
Article
Date
Mar-2001
Author
Kullman L.
Author Affiliation
Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden. leif.kullman@eg.umu.se
Source
Ambio. 2001 Mar;30(2):72-80
Date
Mar-2001
Language
English
Publication Type
Article
Keywords
Climate
Geography
Greenhouse Effect
Humans
Sweden
Trees - growth & development
Abstract
Climate warming by ca. 0.8 degree C between the late-19th and late-20th century, although with some fluctuations, has forced multispecies elevational tree-limit advance by > 100 m for the principal tree species in the Swedish part of the Scandinavian mountain range. Predominantly, these processes imply growth in height of old-established individuals and less frequently upslope migration of new individuals. After a slight retardation during some cooler decades after 1940, a new active phase of tree-limit advance has occurred with a series of exceptionally mild winters and some warm summers during the 1990s. The magnitude of total 20th century tree-limit rise varies with topoclimate and is mainly confined to wind-sheltered and snow-rich segments of the landscape. Thickening of birch tree stands in the "advance belt" has profoundly altered the general character of the subalpine/low alpine landscape and provides a positive feedback loop for further progressive change and resilience to short-term cooling episodes. All upslope tree-limit shifts and associated landscape transformations during the 20th century have occurred without appreciable time lags, which constitutes knowledge fundamental to the generation of realistic models concerning vegetation responses to potential future warming. The new and elevated pine tree-limit may be the highest during the past 4000 14C years. Thus, it is tentatively inferred that the 20th century climate is unusually warm in a late-Holocene perspective.
PubMed ID
11374309 View in PubMed
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(137)Cs distributions in soil and trees in forest ecosystems after the radioactive fallout - Comparison study between southern Finland and Fukushima, Japan.

https://arctichealth.org/en/permalink/ahliterature281005
Source
J Environ Radioact. 2016 Sep;161:73-81
Publication Type
Article
Date
Sep-2016
Author
Jukka Pumpanen
Mizue Ohashi
Izuki Endo
Pertti Hari
Jaana Bäck
Markku Kulmala
Nobuhito Ohte
Source
J Environ Radioact. 2016 Sep;161:73-81
Date
Sep-2016
Language
English
Publication Type
Article
Keywords
Cesium Radioisotopes - analysis
Chernobyl Nuclear Accident
Cryptomeria
Finland
Fukushima Nuclear Accident
Japan
Pinus
Plant Leaves - chemistry
Plant Stems - chemistry
Radioactive fallout
Soil Pollutants, Radioactive - analysis
Trees - chemistry
Abstract
The nuclear accidents at Chernobyl and Fukushima released large amounts of (137)Cs radionuclides into the atmosphere which spread over large forest areas. We compared the (137)Cs concentration distribution in different parts of two coniferous forest ecosystems (needle litter, stems and at different depths in the soil) over short and long term periods in Finland and Japan. We also estimated the change in (137)Cs activity concentrations in needle and soil between 1995 and 2013 in Southern Finland based on the back-calculated (137)Cs activity concentrations. We hypothesized that if the (137)Cs activity concentrations measured in 1995 and 2013 showed a similar decline in concentration, the (137)Cs activity concentration in the ecosystem was already stable in 1995. But if not, the (137)Cs activity concentrations were still changing in 2013. Our results showed that the vertical distribution of the (137)Cs fallout in the soil was similar in Hyytiälä and Fukushima. The highest (137)Cs concentrations were observed in the uppermost surface layers of the soil, and they decreased exponentially deeper in the soil. We also observed that (137)Cs activity concentrations estimated from the samples in 1995 and 2013 in Finland showed different behavior in the surface soil layers compared to the deep soil layer. These results suggested that the (137)Cs nuclei were still mobile in the surface soil layers 27 years after the accident. Our results further indicated that, in the aboveground parts of the trees, the (137)Cs concentrations were much closer to steady-state when compared to those of the surface soil layers based on the estimated declining rates of (137)Cs concentration activity in needles which were similar in 1995 and 2013. Despite its mobility and active role in the metabolism of trees, the (137)Cs remains in the structure of the trees for decades, and there is not much exchange of (137)Cs between the heartwood and surface layers of the stem.
PubMed ID
27158060 View in PubMed
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A 700-year paleoecological record of boreal ecosystem responses to climatic variation from Alaska.

https://arctichealth.org/en/permalink/ahliterature85780
Source
Ecology. 2008 Mar;89(3):729-43
Publication Type
Article
Date
Mar-2008
Author
Tinner Willy
Bigler Christian
Gedye Sharon
Gregory-Eaves Irene
Jones Richard T
Kaltenrieder Petra
Krähenbühl Urs
Hu Feng Sheng
Author Affiliation
Institute of Plant Sciences and Oeschger Center for Climate Change Research, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland. willy.tinner@ips.unibe.ch
Source
Ecology. 2008 Mar;89(3):729-43
Date
Mar-2008
Language
English
Publication Type
Article
Keywords
Alaska
Climate
Diatoms
Ecosystem
Fires
Forestry
Fossils
Geologic sediments
Greenhouse Effect
Ice Cover
Plant Physiology
Pollen
Time Factors
Trees
Abstract
Recent observations and model simulations have highlighted the sensitivity of the forest-tundra ecotone to climatic forcing. In contrast, paleoecological studies have not provided evidence of tree-line fluctuations in response to Holocene climatic changes in Alaska, suggesting that the forest-tundra boundary in certain areas may be relatively stable at multicentennial to millennial time scales. We conducted a multiproxy study of sediment cores from an Alaskan lake near the altitudinal limits of key boreal-forest species. Paleoecological data were compared with independent climatic reconstructions to assess ecosystem responses of the forest tundra boundary to Little Ice Age (LIA) climatic fluctuations. Pollen, diatom, charcoal, macrofossil, and magnetic analyses provide the first continuous record of vegetation fire-climate interactions at decadal to centennial time scales during the past 700 years from southern Alaska. Boreal-forest diebacks characterized by declines of Picea mariana, P. glauca, and tree Betula occurred during the LIA (AD 1500-1800), whereas shrubs (Alnus viridis, Betula glandulosa/nana) and herbaceous taxa (Epilobium, Aconitum) expanded. Marked increases in charcoal abundance and changes in magnetic properties suggest increases in fire importance and soil erosion during the same period. In addition, the conspicuous reduction or disappearance of certain aquatic (e.g., Isoetes, Nuphar, Pediastrum) and wetland (Sphagnum) plants and major shifts in diatom assemblages suggest pronounced lake-level fluctuations and rapid ecosystem reorganization in response to LIA climatic deterioration. Our results imply that temperature shifts of 1-2 degrees C, when accompanied by major changes in moisture balance, can greatly alter high-altitudinal terrestrial, wetland, and aquatic ecosystems, including conversion between boreal-forest tree line and tundra. The climatic and ecosystem variations in our study area appear to be coherent with changes in solar irradiance, suggesting that changes in solar activity contributed to the environmental instability of the past 700 years.
PubMed ID
18459336 View in PubMed
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The 2005 Canadian Hypertension Education Program recommendations for the management of hypertension: part 1- blood pressure measurement, diagnosis and assessment of risk.

https://arctichealth.org/en/permalink/ahliterature173955
Source
Can J Cardiol. 2005 Jun;21(8):645-56
Publication Type
Article
Date
Jun-2005
Author
Brenda R Hemmelgarn
Finlay A McAllister
Martin G Myers
Donald W McKay
Peter Bolli
Carl Abbott
Ernesto L Schiffrin
Steven Grover
George Honos
Marcel Lebel
Karen Mann
Thomas Wilson
Brian Penner
Guy Tremblay
Sheldon W Tobe
Ross D Feldman
Author Affiliation
Division of Nephrology, University of Calgary, Calgary, Canada.
Source
Can J Cardiol. 2005 Jun;21(8):645-56
Date
Jun-2005
Language
English
Publication Type
Article
Keywords
Blood Pressure Monitoring, Ambulatory
Canada
Decision Trees
Evidence-Based Medicine
Humans
Hypertension - diagnosis - prevention & control
Patient Education as Topic
Risk assessment
Abstract
To provide updated, evidence-based recommendations for the diagnosis and assessment of adults with high blood pressure (BP).
For persons in whom a high BP value is recorded, the assignment of a diagnosis of hypertension is dependent on the appropriate measurement of BP, the level of the BP elevation and the duration of follow-up. In addition, the presence of cardiovascular risk factors and target organ damage should be assessed to determine the urgency, intensity and type of treatment. For persons diagnosed as having hypertension, estimating overall risk of adverse cardiovascular outcomes requires an assessment of other vascular risk factors and hypertensive target organ damage.
MEDLINE searches were conducted from November 2003 to October 2004 to update the 2004 recommendations. Reference lists were scanned, experts were polled, and the personal files of the authors and subgroup members were used to identify other studies. Identified articles were reviewed and appraised using prespecified levels of evidence by content and methodological experts. As per previous years, only studies that had been published in the peer-reviewed literature were included; evidence from abstracts, conference presentations and unpublished personal communications was not included.
This document contains recommendations for BP measurement, diagnosis of hypertension and assessment of cardiovascular risk for adults with high BP. These include the accurate measurement of BP, criteria for diagnosis of hypertension, and recommendations for follow-up, assessment of overall cardiovascular risk, routine and optional laboratory testing, assessment for renovascular and endocrine causes, home and ambulatory BP monitoring, and the role of echocardiography for those with hypertension. Key features of the 2005 recommendations include an expedited diagnostic algorithm for hypertension and an endorsement of the use of home/self and ambulatory BP assessment as validated techniques in establishing the diagnosis of hypertension.
All recommendations were graded according to the strength of the evidence and voted on by the 43 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported in the present paper received at least 95% consensus. These guidelines will continue to be updated annually.
PubMed ID
16003448 View in PubMed
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4200 years of pine-dominated upland forest dynamics in west-central Mexico: human or natural legacy?

https://arctichealth.org/en/permalink/ahliterature155658
Source
Ecology. 2008 Jul;89(7):1893-907
Publication Type
Article
Date
Jul-2008
Author
Blanca L Figueroa-Rangel
Katherine J Willis
Miguel Olvera-Vargas
Author Affiliation
Oxford Long-term Ecology Laboratory, Oxford University Centre for the Environment, School of Geography, South Parks Road, Oxford, OX1 3QY, United Kingdom. bfrangel@cucsur.udg.mx
Source
Ecology. 2008 Jul;89(7):1893-907
Date
Jul-2008
Language
English
Publication Type
Article
Keywords
Climate
Ecosystem
Fossils
Human Activities
Humans
Mexico
Paleontology
Pinus - physiology
Pollen
Population Dynamics
Soil
Time Factors
Trees - physiology
Abstract
The pine-dominated forests of west-central Mexico are internationally recognized for their high biodiversity, and some areas are protected through various conservation measures including prohibition of human activity. In this region, however, there is evidence for human settlement dating back to ca. AD 1200. It is therefore unclear whether the present forest composition and structure are part of a successional stage following use by indigenous human populations during the past, or due to natural processes, such as climate. We present a study reconstructing the vegetation dynamics of pine-dominated forest over the past 4200 years using paleoecological techniques. Results from fossil pollen and charcoal indicate that, in this region, pine-dominated forests are the native vegetation type and not anthropogenically derived secondary succession. The predominant driving mechanism for the expansion of pine-dominated forest appears to be intervals of aridity and naturally induced burning. A close association is noted between pine abundance and longer-term climatic trends, including intervals of aridity between ca. 4200 and 2500, 1200 and 850, and 500 and 200 cal yr BP and shorter-term trends. Evident periodicity occurs in pine and Poaceae abundance every 80 years. These short-term quasi-periodic oscillations have been recorded in a number of lake and ocean sediments in Mexico and are thought to be linked to solar forcing resulting in drought cycles that occur at approximately the same time intervals.
PubMed ID
18705376 View in PubMed
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Abnormal Papanicolaou smears and colposcopic follow-up among American Indian and Alaska Native women in the Pacific northwest.

https://arctichealth.org/en/permalink/ahliterature4082
Source
J Am Board Fam Pract. 1995 May-Jun;8(3):183-8
Publication Type
Article
Author
T J Gilbert
J R Sugarman
N. Cobb
Author Affiliation
Fred Hutchinson Cancer Research Center, Division of Public Health Services, Seattle, WA, USA.
Source
J Am Board Fam Pract. 1995 May-Jun;8(3):183-8
Language
English
Publication Type
Article
Keywords
Alaska
Cervical Intraepithelial Neoplasia - ethnology - pathology
Colposcopy
Decision Trees
Female
Follow-Up Studies
Humans
Indians, North American
Northwestern United States
Prevalence
Research Support, U.S. Gov't, P.H.S.
Retrospective Studies
Uterine Cervical Neoplasms - ethnology - pathology
Vaginal Smears
Abstract
BACKGROUND: Mortality that is due to cervical cancer among American Indian and Alaska Native women in the Pacific Northwest exceeds that among women of other races. Nevertheless, little information is available regarding the prevalence and follow-up of abnormal Papanicolaou smears among American Indian and Alaska Native women in the region. METHODS: We conducted a retrospective review of medical records of American Indian and Alaska Native women seen at 12 Indian Health Service and tribally operated clinics in Washington, Oregon, and Idaho who had an abnormal Papanicolaou smear in 1992. RESULTS: Of 4547 Papanicolaou smear results reviewed, 280 (6.2 percent) had an abnormal result (dysplasia or carcinoma in situ). Of the recommended colposcopies, 167 of 224 (75 percent) were completed. Women with high-grade squamous intraepithelial lesions were more likely to obtain recommended colposcopy than were women with low-grade squamous intraepithelial lesions. Women treated at clinics that referred patients to outside providers for colposcopy were more likely to have colposcopy than were those who were offered the procedure on site. CONCLUSIONS: The proportion of Pacific Northwest American Indian and Alaska Native women in Indian Health Service and tribal clinics with abnormal Papanicolaou smears and the proportion who receive colposcopy are similar to those in other populations. The higher rate of cervical cancer mortality among American Indian and Alaska Native women could be due to failure to screen high-risk women. Cytologic screening rates, methods to improve adherence to colposcopy recommendations, and the contribution of other factors to the cause of cervical cancer mortality need to be characterized in this population.
PubMed ID
7618496 View in PubMed
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Source
Duodecim. 2013;129(13):1346-50
Publication Type
Article
Date
2013
Author
Matti Hannuksela
Author Affiliation
ihotautien ja allergologian erikoisliekari Helsinki.
Source
Duodecim. 2013;129(13):1346-50
Date
2013
Language
Finnish
Publication Type
Article
Keywords
Allergens - immunology
Finland
Humans
Hypersensitivity - immunology
Immunoglobulin E - immunology
Lichens - immunology
Rhinitis, Allergic, Seasonal - immunology
Seasons
Spores - immunology
Trees - immunology
Abstract
In the summer forest there are allergens and irritating substances that cause respiratory or cutaneous symptoms. Birch and alder pollen allergy is common in Finland. Pollens of other trees cause sensitization only sporadically. Spores of molds and mushrooms cause allergic reactions, but the means to study spore allergy are inadequate. Even edible mushrooms may cause allergic abdominal discomforts, and trehalose intolerance is supposed to be present in a small percentage of the population. Lichen allergens may bring about IgE-mediated reactions, contact allergy and photoallergic reactions.
PubMed ID
23901735 View in PubMed
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Aboveground and belowground legacies of native Sami land use on boreal forest in northern Sweden 100 years after abandonment.

https://arctichealth.org/en/permalink/ahliterature104173
Source
Ecology. 2014 Apr;95(4):963-77
Publication Type
Article
Date
Apr-2014
Author
Grégoire T Freschet
Lars Ostlund
Emilie Kichenin
David A Wardle
Source
Ecology. 2014 Apr;95(4):963-77
Date
Apr-2014
Language
English
Publication Type
Article
Keywords
Arctic Regions
Ecosystem
Environment
Environmental monitoring
Human Activities
Humans
Population Groups
Soil
Sweden
Time Factors
Trees - physiology
Abstract
Human activities that involve land-use change often cause major transformations to community and ecosystem properties both aboveground and belowground, and when land use is abandoned, these modifications can persist for extended periods. However, the mechanisms responsible for rapid recovery vs. long-term maintenance of ecosystem changes following abandonment remain poorly understood. Here, we examined the long-term ecological effects of two remote former settlements, regularly visited for -300 years by reindeer-herding Sami and abandoned -100 years ago, within an old-growth boreal forest that is considered one of the most pristine regions in northern Scandinavia. These human legacies were assessed through measurements of abiotic and biotic soil properties and vegetation characteristics at the settlement sites and at varying distances from them. Low-intensity land use by Sami is characterized by the transfer of organic matter towards the settlements by humans and reindeer herds, compaction of soil through trampling, disappearance of understory vegetation, and selective cutting of pine trees for fuel and construction. As a consequence, we found a shift towards early successional plant species and a threefold increase in soil microbial activity and nutrient availability close to the settlements relative to away from them. These changes in soil fertility and vegetation contributed to 83% greater total vegetation productivity, 35% greater plant biomass, and 23% and 16% greater concentrations of foliar N and P nearer the settlements, leading to a greater quantity and quality of litter inputs. Because decomposer activity was also 40% greater towards the settlements, soil organic matter cycling and nutrient availability were further increased, leading to likely positive feedbacks between the aboveground and belowground components resulting from historic land use. Although not all of the activities typical of Sami have left visible residual traces on the ecosystem after 100 years, their low-intensity but long-term land use at settlement sites has triggered a rejuvenation of the ecosystem that is still present. Our data demonstrates that aboveground-belowground interactions strongly control ecosystem responses to historical human land use and that medium- to long-term consequences of even low-intensity human activities must be better accounted for if we are to predict and manage ecosystems succession following land-use abandonment.
PubMed ID
24933815 View in PubMed
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Accumulation of 137Cesium and 90Strontium from abiotic and biotic sources in rodents at Chornobyl, Ukraine.

https://arctichealth.org/en/permalink/ahliterature61733
Source
Environ Toxicol Chem. 2001 Sep;20(9):1927-35
Publication Type
Article
Date
Sep-2001
Author
R K Chesser
B E Rodgers
J K Wickliffe
S. Gaschak
I. Chizhevsky
C J Phillips
R J Baker
Author Affiliation
Department of Genetics, University of Georgia, Athens 30602, USA. rchesser@ttu.edu
Source
Environ Toxicol Chem. 2001 Sep;20(9):1927-35
Date
Sep-2001
Language
English
Publication Type
Article
Keywords
Accidents, Radiation
Animals
Animals, Wild
Arvicolinae
Cesium radioisotopes - pharmacokinetics
Diet
Environmental monitoring
Female
Male
Mice
Power Plants
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Soil Pollutants, Radioactive - pharmacokinetics
Strontium Radioisotopes - pharmacokinetics
Tissue Distribution
Trees
Ukraine
Abstract
Bank voles (Clethrionomys glareolus) and laboratory strains of house mice (Mus musculus BALB and C57BL) were relocated into enclosures in a highly contaminated area of the Red Forest near the Chornobyl (Ukraine) Reactor 4 to evaluate the uptake rates of 137Cs and 90Sr from abiotic sources. Mice were provided with uncontaminated food supplies, ensuring that uptake of radionuclides was through soil ingestion, inhalation, or water. Mice were sampled before introduction and were reanalyzed every 10 d for 137Cs uptake. Levels of 90Sr were assessed in subsamples from the native populations and in experimental animals at the termination of the study. Uptake rates in house mice were greater than those in voles for both 137Cs and 90Sr. Daily uptake rates in house mice were estimated at 2.72 x 10(12) unstable atoms per gram (whole body) for 137Cs and 4.04 x 10(10) unstable atoms per gram for 90Sr. Comparable rates in voles were 2.26 x 10(11) unstable atoms per gram for 137Cs and 1.94 x 10(10) unstable atoms per gram for 90Sr. By comparing values from voles in the enclosures to those from wild voles caught within 50 m of the enclosures, it was estimated that only 8.5% of 137Cs was incorporated from abiotic sources, leaving 91.5% being incorporated by uptake from biotic materials. The fraction of 90Sr uptake from abiotic sources was at least 66.7% (and was probably much higher). Accumulated whole-body doses during the enclosure periods were estimated as 174 mGy from intramuscular 137Cs and 68 mGy by skeletal 90Sr in house mice over 40 d and 98 mGy from 137Cs and 19 mGy from 90Sr in voles over 30 d. Thus, uptake of radionuclides from abiotic materials in the Red Forest at Chornobyl is an important source of internal contamination.
PubMed ID
11521818 View in PubMed
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Accurate molecular classification of kidney cancer subtypes using microRNA signature.

https://arctichealth.org/en/permalink/ahliterature137534
Source
Eur Urol. 2011 May;59(5):721-30
Publication Type
Article
Date
May-2011
Author
Youssef M Youssef
Nicole M A White
Jörg Grigull
Adriana Krizova
Christina Samy
Salvador Mejia-Guerrero
Andrew Evans
George M Yousef
Author Affiliation
Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada.
Source
Eur Urol. 2011 May;59(5):721-30
Date
May-2011
Language
English
Publication Type
Article
Keywords
Adenoma, Oxyphilic - classification - diagnosis - genetics
Carcinoma, Renal Cell - classification - diagnosis - genetics
Cluster analysis
Decision Trees
Diagnosis, Differential
Gene Expression Profiling - methods
Gene Expression Regulation, Neoplastic
Genetic Testing - methods
Humans
Kidney Neoplasms - classification - diagnosis - genetics
MicroRNAs - analysis
Oligonucleotide Array Sequence Analysis
Ontario
Predictive value of tests
Reproducibility of Results
Reverse Transcriptase Polymerase Chain Reaction
Terminology as Topic
Tumor Markers, Biological - genetics
Abstract
Renal cell carcinoma (RCC) encompasses different histologic subtypes. Distinguishing between the subtypes is usually made by morphologic assessment, which is not always accurate.
Our aim was to identify microRNA (miRNA) signatures that can distinguish the different RCC subtypes accurately.
A total of 94 different subtype cases were analysed. miRNA microarray analysis was performed on fresh frozen tissues of three common RCC subtypes (clear cell, chromophobe, and papillary) and on oncocytoma. Results were validated on the original as well as on an independent set of tumours, using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis with miRNA-specific primers.
Microarray data were analysed by standard approaches. Relative expression for qRT-PCR was determined using the ??C(T) method, and expression values were normalised to small nucleolar RNA, C/D box 44 (SNORD44, formerly RNU44). Experiments were done in triplicate, and an average was calculated. Fold change was expressed as a log(2) value. The top-scoring pairs classifier identified operational decision rules for distinguishing between different RCC subtypes and was robust under cross-validation.
We developed a classification system that can distinguish the different RCC subtypes using unique miRNA signatures in a maximum of four steps. The system has a sensitivity of 97% in distinguishing normal from RCC, 100% for clear cell RCC (ccRCC) subtype, 97% for papillary RCC (pRCC) subtype, and 100% accuracy in distinguishing oncocytoma from chromophobe RCC (chRCC) subtype. This system was cross-validated and showed an accuracy of about 90%. The oncogenesis of ccRCC is more closely related to pRCC, whereas chRCC is comparable with oncocytoma. We also developed a binary classification system that can distinguish between two individual subtypes.
MiRNA expression patterns can distinguish between RCC subtypes.
Notes
Comment In: Eur Urol. 2011 May;59(5):731-321296486
PubMed ID
21272993 View in PubMed
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592 records – page 1 of 60.