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Minnesota
Kinds of Minnesota Terms modified by Minnesota Selected AbstractsEFFECTS OF PRESCRIPTIVE RIPARIAN BUFFERS ON LANDSCAPE CHARACTERISTICS IN NORTHERN MINNESOTA, USA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2002JoAnn M. Hanowski ABSTRACT: Forest buffers adjacent to water bodies are widely prescribed in forest management to protect ecological functions of riparian systems. To date, buffers have been applied on the landscape uniformly without quantifying their effectiveness or the effects they have on landscape characteristics. Our objective was to quantify landscape characteristics (amount of edge and interior forest) when buffers were applied to water bodies in a 100 by 100 km area of northern Minnesota. We used a Landsat classified image in a geographic information system platform to apply two buffer widths ,28.5 m and 57 m , to water bodies, including nonforested wetlands, intermittent or perennial streams, and lakes. A total of 107,141 ha (18.3 percent) of the forest area was adjacent to and within 28.5 m of these water bodies, while 201,457 ha of forest was within 57 m, representing 34.4 percent of the total forest area. Imposing a 28.5 m buffer on water bodies increased the amount of edge and interior forest in the study area. When water bodies were buffered with a 57 m forest strip, we found a slight increase in forest edge from the current condition, and this buffer width resulted in the largest amount of interior forest. Interior forest increased with the 57 m buffer due to the density of water bodies in this region; adjacent water bodies coalesced when buffers were applied and formed isolated forest islands that contained forest interior habitat. Instead of wholesale application of set width riparian buffers, we suggest that ecological conditions of riparian areas be evaluated on a site level and that areas that currently provide important riparian conditions be maintained on the landscape with appropriate management practices. [source] Recreational Portage Trails as Corridors Facilitating Non-Native Plant Invasions of the Boundary Waters Canoe Area Wilderness (U.S.A.)CONSERVATION BIOLOGY, Issue 5 2005SARA JO M. DICKENS corredores; invasiones; perturbación humana; recreación; senderos Abstract:,Wilderness areas are protected and valued in part for recreation; recreational use, however, can negatively impact these areas. In particular, recreational use can facilitate transport of non-native propagules and create open sites for establishment of non-native species. We examined the role of recreational portage trails in the introduction and establishment of non-native plants into the Boundary Waters Canoe Area Wilderness of northern Minnesota (U.S.A.). On 20 portages, we sampled non-native plant richness and cover at four distances (0, 10, 25, and 50 m) from trails. Non-native richness and cover were not related to distance from wilderness entry point. Non-native richness and cover were, however, negatively related to distance from trails. All six non-native species we observed were either directly on or within 1 m of trails. These results suggest that recreational trails act as corridors facilitating invasions of non-native plants into wilderness areas. It remains unclear, however, whether these effects are caused by dispersal of propagules, creation of bare ground, or changes in the native plant community. Resumen:,En parte, las áreas silvestres son protegidas y valoradas para recreación; sin embargo, el uso recreativo puede impactar a estas áreas negativamente. En particular, el uso recreativo puede facilitar el transporte de propágulos no nativos y crear áreas abiertas para el establecimiento de especies no nativas. Examinamos el papel de senderos recreativos en la introducción y establecimiento de plantas no nativas en el Boundary Waters Canoe Area Wilderness en el norte de Minnesota (E.U.A.). En 20 senderos, muestreamos la riqueza y cobertura de plantas no nativas a cuatro distancias (0, 10, 25 y 50 m) de los senderos. La riqueza y cobertura de no nativas no se relacionaron con la distancia al punto de entrada al área silvestre. Sin embargo, la riqueza y cobertura de no nativas se relacionaron negativamente con la distancia a los senderos. Las seis especies no nativas fueron observadas directamente sobre o a 1 m de los senderos. Estos resultados sugieren que los senderos recreativos fungen como corredores que facilitan la invasión de plantas no nativas a las áreas silvestres. Sin embargo, aún no es claro si estos efectos son causados por la dispersión de propágulos, la creación de suelo desnudo o por cambios en la comunidad de plantas nativas. [source] Mohs Micrographic Surgery for Lentigo Maligna and Lentigo Maligna Melanoma using Mel-5 Immunostaining: University of Minnesota ExperienceDERMATOLOGIC SURGERY, Issue 5 2006SACHIN S. BHARDWAJ MD BACKGROUND Mohs micrographic surgery (MMS) continues to become a more common and accepted treatment for lentigo maligna (LM) and lentigo maligna melanoma (LMM). The primary difficulty encountered lies in the accurate identification of atypical single melanocytes to determine tumor-free margins. Numerous methods have been used to better visualize single melanocytes, with varying results. We present our experience using Mel-5 immunostaining in MMS of LM and LMM. METHODS Two hundred patients with primary or recurrent LM or LMM were treated using MMS from 1999 to 2003 at the University of Minnesota. The initial clinical margins were determined by Wood's light examination, and an initial debulk specimen was taken and sent for formalin fixation and later reviewed by a dermatopathologist. The first Mohs layer was then taken, and staining with hemotoxylin and eosin as well as Mel-5 immunostaining was performed. All patients were followed up to evaluate for recurrence, with a mean follow-up time of 38.4 months. RESULTS Of the 200 patients treated, only one recurrence was noted. This patient had been treated with excision followed by radiation before MMS. Use of Mel-5 immunostaining added approximately 40 minutes to each stage. Use of the Autostainer Immunostaining System (DAKO, Carpenterina, CA, USA) shortened the added time to 20 minutes. CONCLUSIONS MMS with Mel-5 immunostaining yielded excellent results in the treatment of LM and LMM, with only one recurrence noted in 200 patients. When an automated immunostainer was used, minimal time was added to each Mohs stage. [source] Survival of individuals with cerebral palsy receiving continuous intrathecal baclofen treatment: a matched-cohort studyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2010LINDA E KRACH Aim, To determine whether intrathecal baclofen (ITB) changes mortality risk in persons with cerebral palsy (CP). Method, Records were reviewed for all persons with CP who were managed with ITB for hypertonicity at a specialty hospital in Minnesota between May 1993 and August 2007. A comparison cohort was randomly selected from clients of the California Department of Developmental Services who were initially evaluated between 1987 and 1990 and were matched to those with ITB for age, sex, Gross Motor Function Classification System (GMFCS) level, presence or absence of epilepsy, and feeding-tube use. Survival probabilities were estimated using the Kaplan,Meier method, and differences were tested via log-rank. Results, Three hundred and fifty-nine persons with CP (202 males, 157 females) receiving ITB for hypertonicity (mean age 12y 8mo, SD 7y 9mo, range 3y 1mo to 39y 9mo) were matched to 349 persons without ITB pumps (195 males, 154 females; mean age 12y 7mo, SD 8y 4mo, range 2y 7mo to 40y). The proportion of patients at different GMFCS levels in the ITB and in the non-ITB cohorts, respectively, was as follows: level II 3% and 3%, level III 16% and 16%, level IV 38% and 37%, and level V 43% and 44%. Survival at 8 years of follow-up was 92% (SD 1.9%) in the ITB cohort and 82% (SD 2.4%) in the non-ITB cohort (p<0.001). After adjustment to account for recent trends in improved survival in CP, 8-year survival in the non-ITB cohort was 88%, which was not significantly different from the ITB cohort (p=0.073). Interpretation, ITB therapy does not increase mortality in individuals with CP and may suggest an increase in life expectancy. [source] Landscape composition influences patterns of native and exotic lady beetle abundanceDIVERSITY AND DISTRIBUTIONS, Issue 4 2009M. M. Gardiner Abstract Aim, Coccinellid beetles are important predators that contribute to pest suppression in agricultural landscapes. Since the introduction of the exotic coccinellids Coccinella septempunctata L. and Harmonia axyridis Pallas into the USA, several studies have reported a decline of native Coccinellidae in agroecosystems. We aimed to investigate the influence of landscape composition on native and exotic coccinellid abundance within soybean fields. Location, Iowa, Michigan, Minnesota and Wisconsin. Methods, As part of a 2-year study (2005,06) on the biological control of the soybean aphid, Aphis glycines Matsumura, we examined coccinellid communities in 33 soybean fields using yellow sticky card traps. Landscape heterogeneity and composition were measured at multiple spatial scales ranging 1,3.5 km from focal soybean fields where coccinellid sampling took place. Results, Exotic species made up 90% of the total coccinellid community in Michigan soybean fields followed by Wisconsin (84%), Minnesota (66%) and Iowa (57%). Harmonia axyridis was the dominant exotic coccinellid in all states comprising 45,62% of the total coccinellid community, followed by C. septempunctata (13,30%). Two additional exotic species, Hippodamia variegata (Goeze) and Propylea quatuordecimpunctata (L.) were also found in the region. Overall, the most abundant native coccinellid was Hippodamia convergens Guerin-Meneville; however, its abundance varied across the region, comprising 0% (Michigan) to 28% (Iowa) of the total coccinellid community. Landscape structure significantly influenced the composition of coccinellid communities in soybean agroecosystems. We found that native coccinellids were most abundant in low-diversity landscapes with an abundance of grassland habitat while exotic coccinellids were associated with the abundance of forested habitats. Main conclusion, We propose that grassland dominated landscapes with low structural diversity and low amounts of forested habitat may be resistant to exotic coccinellid build-up, particularly H. axyridis and therefore represent landscape-scale refuges for native coccinellid biodiversity. [source] Multi-phase evolution of gnammas (weathering pits) in a Holocene deglacial granite landscape, Minnesota (USA)EARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2008David Domínguez-Villar Abstract The morphometry of 85 gnammas (weathering pits) from Big Stone County in western Minnesota allows the assessment of the relative ages of the gnamma population. The ratio between maximum and minimum depths is independent of the initial size of the cavity and only depends on the weathering evolution. Therefore, the distribution of depth ratios can be used to assess the gnamma population age and the history of weathering. The asymmetrical distribution of depth ratios measured in Big Stone County forms three distinct populations. When these sets are analyzed independently, the correlation (r2) between maximum and minimum depths is greater than 0·95. Each single population has a normal distribution of depth ratios and the average depth ratios (, -value) for each population are ,1 = 1·60 ± 0·05, ,2 = 2·09 ± 0·04 and ,3 = 2·42 ± 0·08. The initiation of gnamma formation followed the exhumation of the granite in the region. This granite was till and saprolite covered upon retreat of the ice from the Last Glacial Maximum. Nearby outcrops are striated, but the study site remained buried until it was exhumed by paleofloods issuing from a proglacial lake. These Holocene-aged gnammas in western Minnesota were compared with gnammas of other ages from around the world. Our new results are in accordance with the hypothesis that , -values represent the evolution of gnammas with time under temperate- to cold-climate dynamics. Phases of the formation of new gnammas may result from changes in weathering processes related to climate changes. Copyright © 2007 John Wiley & Sons, Ltd. [source] Herbivore and pathogen damage on grassland and woodland plants: a test of the herbivore uncertainty principleECOLOGY LETTERS, Issue 4 2002Stefan A. Schnitzer Researchers can alter the behaviour and ecology of their study organisms by conducting such seemingly benign activities as non-destructive measurements and observations. In plant communities, researcher visitation and measurement of plants may increase herbivore damage in some plant species while decreasing it in others. Simply measuring plants could change their competitive ability by altering the amount of herbivore damage that they suffer. Currently, however, there is only limited empirical evidence to support this `herbivore uncertainty principle' (HUP). We tested the HUP by quantifying the amount of herbivore and pathogen damage in 13 plant species (> 1400 individuals) at four different visitation intensities at Cedar Creek Natural History Area, Minnesota, USA. Altogether, we found very little evidence to support the HUP at any intensity of visitation. Researcher visitation did not alter overall plant herbivore damage or survival and we did not detect a significant visitation effect in any of the 13 species. Pathogen damage also did not significantly vary among visitation treatments, although there was some evidence that high visitation caused slightly higher pathogen damage. Based on our results, we question whether this phenomenon should be considered a `principle' of plant ecology. [source] Parental alcohol dependence and the transmission of adolescent behavioral disinhibition: a study of adoptive and non-adoptive familiesADDICTION, Issue 4 2009Serena M. King ABSTRACT Aim To examine the genetic and environmental influences of parental alcoholism on offspring disinhibited behavior. Design We compared the effect of parental alcoholism history on offspring in adoptive and non-adoptive families. In families with a history of parental alcohol dependence, we examined the effect of exposure to parental alcoholism symptoms during the life-time of the adolescent. Setting Assessments occurred at the University of Minnesota from 1998 to 2004. Participants Adolescents adopted in infancy were ascertained systematically from records of three private Minnesota adoption agencies; non-adopted adolescents were ascertained from Minnesota birth records. Adolescents and their rearing parents participated in in-person assessments. Measurements For adolescents, measures included self- reports of delinquency, deviant peers, substance use, antisocial attitudes and personality. For parents, we conducted DSM-IV clinical assessments of alcohol abuse and dependence. Findings A history of parental alcohol dependence was associated with higher levels of disinhibition only when adolescents were related biologically to their rearing parents. Within families with a history of parental alcoholism, exposure to parental alcohol misuse during the life-time of the adolescent was associated with increased odds of using alcohol in adopted adolescents only. Conclusions These findings suggest that the association between a history of parental alcohol dependence and adolescent offspring behavioral disinhibition is attributable largely to genetic rather than environmental transmission. We also obtained some evidence for parental alcohol misuse as a shared environmental risk factor in adoptive families. [source] RESIN COLLECTION AND SOCIAL IMMUNITY IN HONEY BEESEVOLUTION, Issue 11 2009Michael Simone Diverse animals have evolved an ability to collect antimicrobial compounds from the environment as a means of reducing infection risk. Honey bees battle an extensive assemblage of pathogens with both individual and "social" defenses. We determined if the collection of resins, complex plant secretions with diverse antimicrobial properties, acts as a colony-level immune defense by honey bees. Exposure to extracts from two sources of honey bee propolis (a mixture of resins and wax) led to a significantly lowered expression of two honey bee immune-related genes (hymenoptaecin and AmEater in Brazilian and Minnesota propolis, respectively) and to lowered bacterial loads in the Minnesota (MN) propolis treated colonies. Differences in immune expression were also found across age groups (third-instar larvae, 1-day-old and 7-day-old adults) irrespective of resin treatment. The finding that resins within the nest decrease investment in immune function of 7-day-old bees may have implications for colony health and productivity. This is the first direct evidence that the honey bee nest environment affects immune-gene expression. [source] GEOGRAPHIC VARIATION IN THE EVOLUTION AND COEVOLUTION OF A TRITROPHIC INTERACTIONEVOLUTION, Issue 5 2007Timothy P. Craig The geographic mosaic theory of coevolution predicts that geographic variation in species interactions will lead to differing selective pressures on interacting species, producing geographic variation in the traits of interacting species (Thompson 2005). We supported this hypothesis in a study of the geographic variation in the interactions among Eurosta solidaginis and its natural enemies. Eurosta solidaginis is a fly (Diptera: Tephritidae) that induces galls on subspecies of tall goldenrod, Solidago altissima altissima and S. a. gilvocanescens. We measured selection on E. solidaginis gall size and shape in the prairie and forest biomes in Minnesota and North Dakota over an 11-year period. Galls were larger and more spherical in the prairie than in the forest. We supported the hypothesis that the divergence in gall morphology in the two biomes is due to different selection regimes exerted by natural enemies of E. solidaginis. Each natural enemy exerted similar selection on gall diameter in both biomes, but differences in the frequency of natural enemy attack created strong differences in overall selection between the prairie and forest. Bird predation increased with gall diameter, creating selection for smaller-diameter galls. A parasitic wasp, Eurytoma gigantea, and Mordellistena convicta, an inquiline beetle, both caused higher E. solidaginis mortality in smaller galls, exerting selection for increased gall diameter. In the forest there was stabilizing selection on gall diameter due to a combination of bird predation on larvae in large galls, and M. convicta - and E. gigantea- induced mortality on larvae in small galls. In the prairie there was directional selection for larger galls due to M. convicta and E. gigantea mortality on larvae in small galls. Mordellistena convicta- induced mortality was consistently higher in the prairie than in the forest, whereas there was no significant difference in E. gigantea- induced mortality between biomes. Bird predation was nonexistent in the prairie so the selection against large galls found in the forest was absent. We supported the hypothesis that natural enemies of E. solidaginis exerted selection for spherical galls in both biomes. In the prairie M. convicta exerts stabilizing selection to maintain spherical galls. In the forest there was directional selection for more spherical galls. Eurytoma gigantea exerted selection on gall shape in the forest in a complex manner that varied among years. We also supported the hypothesis that E. gigantea is coevolving with E. solidaginis. The parasitoid had significantly longer ovipositors in the prairie than in the forest, indicating the possibility that it has evolved in response to selection to reach larvae in the larger-diameter prairie galls. [source] The effects of water-level manipulation on the benthic invertebrates of a managed reservoirFRESHWATER BIOLOGY, Issue 5 2010DANIEL C. McEWEN Summary 1. Reservoir creation and management can enhance many ecological services provided by freshwater ecosystems, but may alter the natural conditions to which aquatic biota have adapted. Benthic macroinvertebrates often reflect environmental conditions, and this community may be particularly susceptible to water-level changes that alter sediment exposure, temperature regime, wave-induced sediment redistribution and basal productivity. 2. Using a before,after control,impact experimental design, we assessed changes in macroinvertebrate community structure corresponding with changes in water-level management in two lentic systems in the Voyageurs National Park, Minnesota, U.S.A. Littoral zone (depths 1,5 m) benthic macroinvertebrate assemblages were sampled in Rainy Lake (control system) and Namakan Reservoir (impact system) in 1984,85, and again in 2004,05 following a change in water-level management that began in January 2000. The new regime reduced the magnitude of winter drawdown in Namakan Reservoir from 2.5 to 1.5 m, and allowed the reservoir to fill to capacity in late May, a month earlier than under the prior regime. Rainy Lake water levels were not altered substantially. 3. We found changes in macroinvertebrate community structure in Namakan Reservoir relative to Rainy Lake at 1,2 m depths but not at 3,5 m depths. These shallower depths would have been most directly affected by changes in sediment exposure and ice formation. 4. In 2004,05, Namakan Reservoir benthos showed lower overall abundance, more large-bodied taxa and an increase in non-insect invertebrates relative to 1984,85, without corresponding changes in Rainy Lake. 5. Changes in the benthic community in Namakan may reflect cooler water in spring and early summer as well as lower resource availability (both autochthonous production and allochthonous inputs) under the new regime. [source] Timing of predation by rainbow trout controls Daphnia demography and the trophic status of a Minnesota lakeFRESHWATER BIOLOGY, Issue 6 2005LEIF K. HEMBRE Summary 1. Stocking of lakes with rainbow trout is a common practice that presents a potential conflict for lake managers who must balance the interests of anglers with those concerned that zooplanktivory by trout may trigger a trophic cascade and result in decreased water clarity. 2. This study examined how the timing of trout stocking (autumn versus spring) in a Minnesota (U.S.A.) lake affected (i) the population dynamics of their zooplankton food supply (Daphnia pulicaria), (ii) phytoplankton biomass and water clarity and (iii) trout survival. Sizes of both Daphnia and trout populations were estimated acoustically with high-frequency (192 kHz) sonar. 3. Daphnia were nearly eliminated from the lake during winters after trout were stocked in autumn. In both of these years (1996 and 1997), the Daphnia population was small in the spring, and grew during the summer and into the autumn as the trout population diminished. 4. The lake was then stocked in spring for 2 years (1998 and 1999). This fisheries manipulation alleviated predation over the winter, but increased predation on D. pulicaria during the spring, summer and autumn. However, the high mortality caused by the spring-stocked trout was offset by even higher rates of reproduction by the relatively large populations of fecund Daphnia that survived the winter in 1998 and 1999. 5. Grazing by these dense populations of Daphnia produced clear-water phases during May and June that were inhibited in autumn stocking years. In addition, the large Daphnia populations present during the spring and early summer of 1998 and 1999 provided abundant forage for trout. 6. This fisheries manipulation achieved seemingly mutually exclusive management objectives: a robust planktivorous sport fishery, and clear water for other forms of recreation. [source] Relative influence of variables at multiple spatial scales on stream macroinvertebrates in the Northern Lakes and Forest ecoregion, U.S.A.FRESHWATER BIOLOGY, Issue 8 2003Brian M. Weigel Summary 1We used 94 sites within the Northern Lakes and Forests ecoregion spanning Minnesota, Wisconsin and Michigan to identify environmental variables at the catchment, reach and riparian scales that influence stream macroinvertebrates. Redundancy analyses (RDA) found significantly influential variables within each scale and compared their relative importance in structuring macroinvertebrate assemblages. 2Environmental variables included landcover, geology and groundwater delivery estimates at the catchment scale, water chemistry, channel morphology and stream habitat at the reach scale, and landcover influences at three distances perpendicular to the stream at the riparian scale. Macroinvertebrate responses were characterised with 22 assemblage attributes, and the relative abundance and presence/absence of 66 taxa. 3Each scale defined macroinvertebrates along an erosional to depositional gradient. Wisconsin's macroinvertebrate index of biotic integrity, Ephemeroptera,Plecoptera,Trichoptera taxa and erosional taxa corresponded with forest streams, whereas organic pollution tolerant, Chironomidae and depositional taxa corresponded with wetland streams. Reach scale analyses defined the gradient similarly as dissolved oxygen and wide, shallow channels (erosional) opposed instream macrophytes and pool habitats (depositional). Riparian forests within 30 m of the stream coincided with an erosional assemblage and biotic integrity. 4Next, we combined all significant environmental variables across scales to compare the relative influence of each spatial scale on macroinvertebrates. Partial RDA procedures described how much of the explained variance was attributable to each spatial scale and each interrelated scale combination. 5Our results appeared consistent with the concept of hierarchical functioning of scale in which large-scale variables restrict the potential for macroinvertebrate traits or taxa at smaller spatial scales. Catchment and reach variables were equally influential in defining assemblage attributes, whereas the reach scale was more influential in determining relative abundance and presence/absence. 6Ultimately, comprehending the relative influence of catchment and reach scale properties in structuring stream biota will assist prioritising the scale at which to rehabilitate, manage and derive policies for stream ecosystem integrity. [source] An integrated biogeochemical and economic analysis of bioenergy crops in the Midwestern United StatesGCB BIOENERGY, Issue 5 2010ATUL K. JAIN Abstract This study integrates a biophysical model with a county-specific economic analysis of breakeven prices of bioenergy crop production to assess the biophysical and economic potential of biofuel production in the Midwestern United States. The bioenergy crops considered in this study include a genotype of Miscanthus, Miscanthus×giganteus, and the Cave-in-Rock breed of switchgrass (Panicum virgatum). The estimated average peak biomass yield for miscanthus in the Midwestern states ranges between 7 and 48 metric tons dry matter per hectare per year ( t DM ha,1 yr,1), while that for switchgrass is between 10 and 16 t DM ha,1 yr,1. With the exception of Minnesota and Wisconsin, where miscanthus yields are likely to be low due to cold soil temperatures, the yield of miscanthus is on average more than two times higher than yield of switchgrass. We find that the breakeven price, which includes the cost of producing the crop and the opportunity cost of land, of producing miscanthus ranges from $53 t,1 DM in Missouri to $153 t,1 DM in Minnesota in the low-cost scenario. Corresponding costs for switchgrass are $88 t,1 DM in Missouri to $144 t,1 DM in Minnesota. In the high-cost scenario, the lowest cost for miscanthus is $85 t,1 DM and for switchgrass is $118 t,1 DM, both in Missouri. These two scenarios differ in their assumptions about ease of establishing the perennial crops, nutrient requirements and harvesting costs and losses. The differences in the breakeven prices across states and across crops are mainly driven by bioenergy and row crop yields per hectare. Our results suggest that while high yields per unit of land of bioenergy crops are critical for the competitiveness of bioenergy feedstocks, the yields of the row crops they seek to displace are also an important consideration. Even high yielding crops, such as miscanthus, are likely to be economically attractive only in some locations in the Midwest given the high yields of corn and soybean in the region. [source] The MLH1 ,93 G>A promoter polymorphism and genetic and epigenetic alterations in colon cancerGENES, CHROMOSOMES AND CANCER, Issue 10 2008Wade S. Samowitz The MLH1 ,93 G>A promoter polymorphism has been reported to be associated with an increased risk of microsatellite unstable colorectal cancer. Other than microsatellite instability, however, the genetic and most epigenetic changes of tumors associated with this polymorphism have not been studied. We evaluated associations between the ,93 G>A polymorphism and CpG island methylator phenotype (CIMP), BRAF V600E mutations, and MLH1 methylation in tumors from a sample of 1,211 individuals with colon cancer and 1,968 controls from Utah, Northern California, and Minnesota. The ,93 G>A polymorphism was determined by the five prime nuclease assay. CIMP was determined previously by methylation-specific PCR of CpG islands in MLH1, methylated in tumors (MINT)1, MINT2, MINT31, and CDKN2A (p16). The BRAF V600E mutation was determined by sequencing exon 15. The MLH1 ,93 G>A promoter polymorphism was associated with CIMP (odds ratio (OR) 3.44, 95% confidence interval (CI) 1.85, 6.42), MLH1 methylation (OR 4.16, 95%CI 2.20, 7.86), BRAF mutations (OR 4.26, 95%CI 1.83, 9.91), and older age at diagnosis (OR 3.65, 95%CI 2.08, 6.39) in microsatellite unstable tumors. These associations were not observed in stable tumors. Increased age at diagnosis and tumor characteristics of microsatellite unstable tumors associated with MLH1 ,93 G>A suggests the polymorphism is acting at a relatively late stage of colorectal carcinogenesis to drive CIMP+ tumors down the microsatellite instability pathway. © 2008 Wiley-Liss, Inc. [source] Paramagnetic and ferromagnetic anisotropy of magnetic susceptibility in migmatites: measurements in high and low fields and kinematic implicationsGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2004Eric C. Ferré SUMMARY The separation of paramagnetic and ferromagnetic anisotropy of magnetic susceptibility (AMS) is achieved in this study by using a vibrating sample magnetometer and a torque magnetometer performing directional anisotropy measurements in sufficiently high fields to saturate the ferromagnetic phases. The studied material, a migmatite from Minnesota, has a magnetic mineralogy characterized by ferrimagnetic multidomain titanomagnetite, paramagnetic biotite and a diamagnetic quartzo-feldspathic matrix. The low-field AMS represents the sum of ferromagnetic and paramagnetic contributions because the quartz contribution can be neglected, its magnetic susceptibility being two orders of magnitude smaller than that of biotite. In contrast, measurements in a high field isolate the paramagnetic component of the magnetic fabric. The high-field AMS is consistent between specimens and correlates well with measurements done using the torque magnetometer. The magnetic fabrics of the ferromagnetic and of the paramagnetic minerals are not co-axial, i.e. the subfabrics of the biotite and the magnetite are distinct. We propose that this non-coaxiality is due to a vorticity component during regional deformation and that it reflects the general conditions of deep crustal orogenic deformation. [source] Potential effects of warming and drying on peatland plant community compositionGLOBAL CHANGE BIOLOGY, Issue 2 2003Jake F. Weltzin Abstract Boreal peatlands may be particularly vulnerable to climate change, because temperature regimes that currently constrain biological activity in these regions are predicted to increase substantially within the next century. Changes in peatland plant community composition in response to climate change may alter nutrient availability, energy budgets, trace gas fluxes, and carbon storage. We investigated plant community response to warming and drying in a field mesocosm experiment in northern Minnesota, USA. Large intact soil monoliths removed from a bog and a fen received three infrared warming treatments crossed with three water-table treatments (n = 3) for five years. Foliar cover of each species was estimated annually. In the bog, increases in soil temperature and decreases in water-table elevation increased cover of shrubs by 50% and decreased cover of graminoids by 50%. The response of shrubs to warming was distinctly species-specific, and ranged from increases (for Andromeda glaucophylla) to decreases (for Kalmia polifolia). In the fens, changes in plant cover were driven primarily by changes in water-table elevation, and responses were species- and lifeform-specific: increases in water-table elevation increased cover of graminoids , in particular Carex lasiocarpa and Carex livida, as well as mosses. In contrast, decreases in water-table elevation increased cover of shrubs, in particular A. glaucophylla and Chamaedaphne calyculata. The differential and sometimes opposite response of species and lifeforms to the treatments suggest that the structure and function of both bog and fen plant communities will change , in different directions or at different magnitudes , in response to warming and/or changes in water-table elevation that may accompany regional or global climate change. [source] Effects of Land Use on Ground Water Quality in the Anoka Sand Plain Aquifer of MinnesotaGROUND WATER, Issue 4 2003Michael D. Trojan We began a study, in 1996, to compare ground water quality under irrigated and nonirrigated agriculture, sewered and nonsewered residential developments, industrial, and nondeveloped land uses. Twenty-three monitoring wells were completed in the upper meter of an unconfined sand aquifer. Between 1997 and 2000, sampling occurred quarterly for major ions, trace inorganic chemicals, volatile organic compounds (VOCs), herbicides, and herbicide degradates. On single occasions, we collected samples for polynuclear aromatic hydrocarbons (PAHs), perchlorate, and coliform bacteria. We observed significant differences in water chemistry beneath different land uses. Concentrations of several trace inorganic chemicals were greatest under sewered urban areas. VOC detection frequencies were 100% in commercial areas, 52% in sewered residential areas, and <10% for other land uses. Median nitrate concentrations were greatest under irrigated agriculture (15,350 ,g/L) and nonsewered residential areas (6080 ,g/L). Herbicides and degradates of acetanilide and triazine herbicides were detected in 86% of samples from irrigated agricultural areas, 68% of samples from nonirrigated areas, and <10% of samples from other land uses. Degradates accounted for 96% of the reported herbicide mass. We did not observe seasonal differences in water chemistry, but observed trends in water chemistry when land use changes occurred. Our results show land use is the dominant factor affecting shallow ground water quality. Trend monitoring programs should focus on areas where land use is changing, while resource managers and planners must consider potential impacts of land use changes on ground water quality. [source] Show Us the Money: Lessons in Transparency from State Pharmaceutical Marketing Disclosure LawsHEALTH SERVICES RESEARCH, Issue 1 2010Susan Chimonas Objective. To assess legislation requiring drug companies to report gifts to providers, and to evaluate the information obtained. Data Sources. Data included legislation in Vermont, Minnesota, Maine, Massachusetts, West Virginia, and the District of Columbia, and company disclosure data from Vermont. Study Design. We evaluated the strengths and weaknesses of state legislation. We also analyzed 4 years of company disclosures from Vermont, assessing the value and distribution of industry,provider exchanges and identifying emerging trends in companies' practices. Data Collection Methods. State legislation is publically available. We obtained Vermont's data through requests to the state's Attorney General's office. Principal Findings. Of the state laws, only Vermont's yielded robust, publically available data. These data show gifting was dominated by a few major corporations, and <2 percent of Vermont's prescribers received 69 percent of gifts and payments. Companies were especially generous to specialists in psychiatry, endocrinology/diabetes/metabolism, internal medicine, and neurology. Companies increasingly used loopholes in the law to avoid public scrutiny. Conclusions. Disclosure laws are an important first step in bringing greater transparency to physician,industry relationships. But flaws and weaknesses limit the states' ability to render physician,industry exchanges fully transparent. Future efforts should build on these lessons to render physician,industry relationships fully transparent. [source] Serum aminotransferase activity and mortality risk in a United States community,HEPATOLOGY, Issue 3 2008Tae Hoon Lee Serum aminotransferase [such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT)] is commonly used as an indicator of liver disease. The aim of the study was to determine the degree to which aminotransferase results are associated with increased mortality at the population level. All adult residents of Olmsted County, Minnesota, who had a health care encounter at Mayo Clinic, Rochester, in 1995 were identified and their AST or ALT results extracted from a laboratory database. These subjects were followed forward from January 1995 to April 2006 and their survival determined. To exclude patients with abnormal results because of a terminal illness, deaths within the first 2 years were excluded. The main outcome measure was survival. Standardized mortality ratios (SMRs) were calculated, based on Minnesota White death rates. During 1995, AST was measured at least once in 18,401 community residents, of whom 2,350 (13%) had results greater than the upper limit of normal (ULN). Of 6,823 subjects who had their ALT measured, 911 (13%) had results higher than ULN. Abnormal AST was associated with a significantly increased SMR (1.32 for 1,2× ULN and 1.78 for >2× ULN). SMR was also higher for abnormal ALT (SMR = 1.21 for 1,2× ULN and 1.51 for >2× ULN). In contrast, normal AST or ALT was associated with a risk of death lower than expected (SMR 0.95 for AST, 0.61 for ALT). Conclusion: Serum levels of AST and ALT obtained in a routine medical care setting are associated with future mortality in community residents. (HEPATOLOGY 2008;47:880,887.) [source] Spatiotemporal dynamics of evapotranspiration at the Glacial Ridge prairie restoration in northwestern MinnesotaHYDROLOGICAL PROCESSES, Issue 7 2006Assefa M. Melesse Abstract Among the various indicators of success in wetland restoration, hydrology is the most important and relatively easy to monitor. Evapotranspiration (ET) was used to assess the ecohydrologic changes at the Glacial Ridge prairie restoration site in northwestern Minnesota. Twelve Landsat images from 2000,03 for the months of June, July and August were used to study the spatial ET changes. Spatial monthly and seasonal ET were estimated using a surface energy budget technique from Landsat images. Five sub-basins within the study area were delineated to represent the different conditions of the wetlands. Their spatial and temporal ET responses to the restoration activities (native species planting, burning and ditch closures) were studied. Spatial statistics showing mean and standard deviation of monthly ET were computed. Comparisons were made between these watersheds and the preserved sub-watershed of the study area. The average annual ET increases for the five sub-basins were in the range of 9% (2002,03) to 25% (2001,02). Over the study period, ET increased by nearly 50%. After considering the effect of variations in precipitation, wind speed and solar radiation on the resulting ET, the results show that ET increased in recent years as result of the restoration activities. Copyright © 2005 John Wiley & Sons, Ltd. [source] Characteristics of preferential flow and groundwater discharge to Shingobee Lake, Minnesota, USAHYDROLOGICAL PROCESSES, Issue 10 2002Hans F. Kishel Abstract Small-scale heterogeneities and large changes in hydraulic gradient over short distances can create preferential groundwater flow paths that discharge to lakes. A 170 m2 grid within an area of springs and seeps along the shore of Shingobee Lake, Minnesota, was intensively instrumented to characterize groundwater-lake interaction within underlying organic-rich soil and sandy glacial sediments. Seepage meters in the lake and piezometer nests, installed at depths of 0·5 and 1·0 m below the ground surface and lakebed, were used to estimate groundwater flow. Statistical analysis of hydraulic conductivity estimated from slug tests indicated a range from 21 to 4·8 × 10,3 m day,1 and small spatial correlation. Although hydraulic gradients are overall upward and toward the lake, surface water that flows onto an area about 2 m onshore results in downward flow and localized recharge. Most flow occurred within 3 m of the shore through more permeable pathways. Seepage meter and Darcy law estimates of groundwater discharge agreed well within error limits. In the small area examined, discharge decreases irregularly with distance into the lake, indicating that sediment heterogeneity plays an important role in the distribution of groundwater discharge. Temperature gradients showed some relationship to discharge, but neither temperature profiles nor specific electrical conductance could provide a more convenient method to map groundwater,lake interaction. These results suggest that site-specific data may be needed to evaluate local water budget and to protect the water quality and quantity of discharge-dominated lakes. Copyright © 2002 John Wiley & Sons, Ltd. [source] Update on the incidence and prevalence of Crohn's disease and ulcerative colitis in Olmsted County, Minnesota, 1940,2000,INFLAMMATORY BOWEL DISEASES, Issue 3 2007Conor G. Loftus MD Abstract Background: We previously reported that the prevalence of Crohn's disease (CD) and ulcerative colitis (UC) in Olmsted County, Minnesota, had risen significantly between 1940 and 1993. We sought to update the incidence and prevalence of these conditions in our region through 2000. Methods: The Rochester Epidemiology Project allows population-based studies of disease in county residents. CD and UC were defined by previously used criteria. County residents newly diagnosed between 1990 and 2000 were identified as incidence cases, and persons with these conditions alive and residing in the county on January 1, 2001, were identified as prevalence cases. All rates were adjusted to 2000 US Census figures for whites. Results: In 1990,2000 the adjusted annual incidence rates for UC and CD were 8.8 cases per 100,000 (95% confidence interval [CI], 7.2,10.5) and 7.9 per 100,000 (95% CI, 6.3,9.5), respectively, not significantly different from rates observed in 1970,1979. On January 1, 2001, there were 220 residents with CD, for an adjusted prevalence of 174 per 100,000 (95% CI, 151,197), and 269 residents with UC, for an adjusted prevalence of 214 per 100,000 (95% CI, 188,240). Conclusion: Although incidence rates of CD and UC increased after 1940, they have remained stable over the past 30 years. Since 1991 the prevalence of UC decreased by 7%, and the prevalence of CD increased about 31%. Extrapolating these figures to US Census data, there were ,1.1 million people with inflammatory bowel disease in the US in 2000. (Inflamm Bowel Dis 2007) [source] A population-based study of the frequency of corticosteroid resistance and dependence in pediatric patients with Crohn's disease and ulcerative colitis,INFLAMMATORY BOWEL DISEASES, Issue 12 2006Jeanne Tung MD Abstract Background: The goal of this study was to examine the 1-year outcome after the first course of systemic corticosteroids in an inception cohort of pediatric patients with inflammatory bowel disease. Methods: All Olmsted County (Minnesota) residents diagnosed with Crohn's disease (n = 50) or ulcerative colitis (n = 36) before 19 years of age from 1940 to 2001 were identified. Outcomes at 30 days and 1 year after the initial course of corticosteroids were recorded. Results: Twenty-six patients with Crohn's disease (65%) and 14 with ulcerative colitis (44%) were treated with corticosteroids before age 19. Thirty-day outcomes for corticosteroid-treated Crohn's disease were complete remission in 16 (62%), partial remission in 7 (27%), and no response in 3 (12%), with 2 of these patients requiring surgery. Thirty-day outcomes for treated ulcerative colitis were complete remission in 7 (50%), partial remission in 4 (29%), and no response in 3 (21%). One-year outcomes for Crohn's disease were prolonged response in 11 (42%) and corticosteroid dependence in 8 (31%), whereas 7 (27%) were postsurgical. One-year outcomes for ulcerative colitis were prolonged response in 8 (57%) and corticosteroid dependence in 2 (14%), whereas 4 (29%) were postsurgical. Conclusions: Most pediatric patients with inflammatory bowel disease initially responded to corticosteroids. However, after 1 year, 58% of pediatric patients with Crohn's disease and 43% of pediatric patients with ulcerative colitis either were steroid dependent or required surgery. This finding emphasizes the need for early steroid-sparing medications in pediatric inflammatory bowel disease. [source] Incidence and Prognosis of Colorectal Dysplasia in Inflammatory Bowel Disease: A Population-based Study from Olmsted County, Minnesota,INFLAMMATORY BOWEL DISEASES, Issue 8 2006Tine Jess MD Abstract Background and Aims: The risk, fate, and ideal management of colorectal dysplasia in inflammatory bowel disease (IBD) remain debated. We estimated the incidence, long-term outcome, and risk factors for progression of colorectal dysplasia (adenomas [adenoma-associated lesions or masses (ALMs)], flat dysplasia, and dysplasia-associated lesions or masses [DALMs]) in a population-based IBD cohort from Olmsted County, Minnesota. Materials and Methods: The Rochester Epidemiology Project was used to identify cohort patients with colorectal dysplasia. Medical records were reviewed for demographic and clinical characteristics. Histology slides were reviewed by a pathologist blinded to previous pathology reports. The cumulative incidence of dysplasia was estimated, and the association between patient characteristics and recurrence/progression of dysplasia was assessed using proportional hazards regression. Results: Twenty-nine (4%) IBD patients developed flat dysplasia (n = 8), DALMs (n = 1), ALMs in areas of IBD (n = 18), or ALMs outside areas of IBD (n = 2). Among 6 patients with flat low-grade dysplasia (fLGD) who did not undergo colectomy, none progressed during a median of 17.8 (range 6,21) years of observation with a median of 3 (range 0,12) surveillance colonoscopies. Four (22%) patients with ALMs in areas of IBD who did not undergo surgery developed LGD or DALMs. Primary sclerosing cholangitis and dysplasia located proximal to the splenic flexure were significantly associated with risk for recurrence/progression of dysplasia. Conclusions: This population-based cohort study from Olmsted County, Minnesota did not confirm an increased risk of cancer related to fLGD, whereas 22% of patients with ALMs in areas of IBD developed fLGD or DALMs. [source] Thymidylate synthase polymorphisms and colon cancer: Associations with tumor stage, tumor characteristics and survivalINTERNATIONAL JOURNAL OF CANCER, Issue 10 2007Karen Curtin Abstract Thymidylate synthase (TS) is a key enzyme in folate metabolism, a pathway that is important in colorectal carcinogenesis. We investigated the role of functional polymorphisms in the TS 5,-UTR promoter enhancer region (TSER, 3 or 2 repeats of a 28-bp sequence) and the 3,-UTR (1494delTTAAAG) and their association with colon tumor characteristics, including tumor stage and acquired mutations in p53, Ki- ras and microsatellite instability. Data from a population-based incident case,control colon cancer study in northern California, Utah and Minnesota (1,206 cases, 1,962 controls) was analyzed using unordered polytomous logistic regression models. In both men and women, individuals with variant TS alleles were at reduced risk of having an advanced stage tumor (metastatic disease: OR = 0.35, 95% CI: 0.2,0.6 vs. wildtype TSER and 3,-UTR). Stage-adjusted survival did not differ by genotype. Men with 1 or 2 variant alleles in both the TSER and 3,-UTR genotypes had a 50% reduced risk of a p53 -positive tumor (OR = 0.5, 95% CI: 0.3,0.9 vs. homozygous wildtype TSER and 3,-UTR). Women with 1 or 2 variant alleles for either the TSER or 3,-UTR polymorphism had reduced risk of having any colon tumor that did not vary by mutation status. This study provides some support for associations between TS genotype and colon cancer tumor characteristics. © 2007 Wiley-Liss, Inc. [source] Using NIC to Describe the Role of the Nurse PractitionerINTERNATIONAL JOURNAL OF NURSING TERMINOLOGIES AND CLASSIFICATION, Issue 2003Cindy S. Haugsdal PURPOSE To have nurse practitioners (NPs) identify the 20 most prevalent NIC interventions describing their nursing practice; to determine if the NIC is applicable to the NP role. METHODS The study used a descriptive survey design. NPs with prescriptive privileges in the state of Minnesota received a cover letter and survey that included a description of NIC and a list of the 486 intervention labels and their definitions from the NIC (3rd ed.). Each participant was asked to identify all interventions performed at least once per month in their practice and to provide basic demographic data, including identification of NP specialty. FINDINGS A total of 1,190 surveys were mailed with a return rate of 37%. NPs' average age was 45 years; the average number of years of NP practice was 9. Employment in a clinic represented the work setting of 72% of respondents followed by hospital practice (11%) and long-term care (10%). Specialty (certified) areas were family practice (27%), pediatrics (21%), adult (19%), women's health (16%), geriatrics (11%), psychiatric (5%), and oncology (1%). The educational level was primarily master's degree (73%). NPs identified an average of 120 interventions they performed at least once per month. These interventions reflected areas of patient education and support, as well as documentation and physician collaboration. The 20 most frequently selected interventions were reported by 71%, 90% of respondents. Four core interventions ,"documentation,""telephone consultation,""teaching: prescribed medication," and "emotional support", were used at least once per month by all specialties. DISCUSSION The level of consistency (70%) among responses validates the strong foundation that professional nursing, as described by NIC, provides NPs in their role. Four core interventions and the remaining 16 most frequently selected interventions that are more specific to each specialty practice indicates that NIC is comprehensive enough to meet the needs of a variety of NP practices. CONCLUSIONS NIC encompasses key areas of interventions (health screening, treatment and management, health promotion and education, psychosocial support, indirect activities) central to the role of NPs, but qualitative comments described the need for more language within NIC to characterize the NP role related to the prescribing of medications and treatments. Some respondents found the definitions to be unclear as to whether they were performing or ordering/prescribing the intervention. This lack of clarity could be addressed by further development of the NIC definitions and activities so the advanced role of the NP is more fully described. Development of documentation systems using the core interventions identified by the various NP specialties is needed. Using standardized nursing language for documentation will enable NPs to build clinical databases that reflect and describe the role. Future research needs to be focused by NP specialty and to go beyond the NIC definition and include analysis at the activity level. [source] Culture, Structure, and the Refugee Experience in Somali Immigrant Family TransformationINTERNATIONAL MIGRATION, Issue 1 2010Elizabeth Heger Boyle This analysis suggests a theoretical refinement of migrant acculturation theories to deal specifically with refugee acculturation experiences. Using the case of family dynamics among Somali refugees in Minnesota, we find that the same factors that are theorized to affect voluntary migrants are also important for refugees. Specifically, the nature of exit from the sending society, the reception in a new location, and group characteristics all appear to be important. However, within the category of exit from the sending society, there are specific concerns that will be more relevant to refugees than to "voluntary" migrants. Specifically, the ongoing condition of the sending society and the effects of any transitions on transnational ties are critically important in the refugee context. We demonstrate how the societal upheaval that created the Somali refugee community also affected culture and connections within Somalia, and how this has an ongoing impact on the US Somali refugee community. We argue that it is valuable to refine the acculturation framework when considering refugees. [source] Making Sense of Citizen Diplomats: The People of Duluth, Minnesota, as International ActorsINTERNATIONAL STUDIES PERSPECTIVES, Issue 2 2001Paul Sharp What is citizen diplomacy and how do we assess its significance? These are important questions because of the recent upsurge in international activity of this kind, and because how we answer them says a great deal about how we "do IR." By examining citizen diplomacy in Duluth, Minnesota, this paper offers a typology of citizen diplomats organized around the ideas of who or what they are representing and to whom. Assessing the significance of citizen diplomacy is a more difficult problem since individuals tend to generate a priori answers to it based on our respective theoretical orientations to IR as a whole. As a solution to this problem, the paper proposes a "diplomatic" approach which focuses on both the representation of differences to one another and the professional commitment which diplomats have to maintaining the practices and institutions which make such relations possible. [source] Self-Reported Sleep and Nap Habits and Risk of Falls and Fractures in Older Women: The Study of Osteoporotic FracturesJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2006Katie L. Stone PhD OBJECTIVES: To test the association between self-reported sleep and nap habits and risk of falls and fractures in a large cohort of older women. DESIGN: Study of Osteoporotic Fractures prospective cohort study. SETTING: Clinical centers in Baltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela Valley, near Pittsburgh, Pennsylvania. PARTICIPANTS: Eight thousand one hundred one community-dwelling Caucasian women aged 69 and older (mean 77.0). MEASUREMENTS: Sleep and nap habits were assessed using a questionnaire at the fourth clinic visit (1993/94). Fall frequency during the subsequent year was ascertained using tri-annual questionnaire. Incident hip and nonspinal fractures during 6 years of follow-up were confirmed using radiographic reports. RESULTS: Five hundred fifty-three women suffered hip fractures, and 1,938 suffered nonspinal fractures. In multivariate models, women who reported napping daily had significantly higher odds of suffering two or more falls during the subsequent year (odds ratio=1.32, 95% confidence interval (CI)=1.03,1.69) and were more likely to suffer a hip fracture (hazard ratio (HR)=1.33, 95% CI=0.99,1.78) than women who did not nap daily. Those sleeping at least 10 hours per 24 hours had a higher risk of nonspinal fracture than (HR=1.26, 95% CI=1.00,1.58) and a similar but nonsignificant increased risk of hip fracture to (HR=1.43, 95% CI=0.95,2.15) those who reported sleeping between 8 and 9 hours. CONCLUSION: Self-reported long sleep and daily napping are associated with greater risk of falls and fractures in older women. Interventions to improve sleep may reduce their risk of falls and fractures. Future research is needed to determine whether specific sleep disorders contribute to these relationships. [source] | ||||||||||||||||||||||||||||||||||||||||