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Kinds of Michigan Terms modified by Michigan Selected AbstractsRELATING PHYTOPLANKTON DYNAMICS AND PRODUCTION TO SEDIMENT RESUSPENSION IN SOUTHERN LAKE MICHIGANJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Millie, D. F.1, Fahnenstiel, G. L.2, Carrick, H. J.3, Lohrenz, S. E.4, & Schofield, O. M. E.5 1USDA-Agricultural Research Service, Sarasota, FL 34236, USA, 2NOAA-Lake Michigan Field Station, Muskegon, MI 49441, USA, 3Institute of Marine Science, University of Southern Mississippi, Stennis Space Center, MS 39529, USA, 4Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY 14060, USA; 5Isttitute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road New Brunswick NJ 08901 USA, Sediment resuspension is an annually recurrent feature during spring holomixis in southern Lake Michigan. Relationships between resuspension events and phyt-oplankton biomass, compositional dynamics, and pro-duction were evaluated during 1998 and 1999. Increased water-column light attenuation (KPAR) and suspended particulate matter (SPM) concentrations corresponded with resuspension events within nearshore regions. However, neither KPAR nor SPM corresponded with chlorophyll (Chl) a concentrations, indicating no impact of resuspension on instantaneous biomass accumulation. Diatoms and cryptophytes dominated phytoplankton assemblages and together typically comprised greater than 85% of the Chl a. The associations of SPM/KPAR with diatom Chl a, and the inverse relationship between relative diatom and crypto-phyte Chl a corresponded with the dominance of diatoms and cryptophytes in near- and offshore waters, respectively. Moreover, a spatial variation in species composition occurred during resuspension events; small, centric diatoms exhibiting meroplanktonic life histories and large, pennate diatoms considered benthic in origin were associated with sediment resuspension whereas large, net diatoms and cryptophytes typically comprising phytoplankton of the annual spring bloom and of optically-clear, offshore waters were not. The presence of viable diatom photopigments and the abundance of small centric diatoms within the surficial sediments, established this layer as the source of meroplankton. Integral production was dramatically reduced within sediment-impacted waters; however, nearshore assemblages appeared to have greater photosynthetic capacities than offshore assemblages. Although resuspension dramatically influenced near-shore phytoplankton assemblages, it appeared to have little, if any relationship with the compositional development of the annual spring bloom. [source] Graphical user interfaces in an engineering educational environmentCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 1 2005Christopher Depcik Abstract Graphical user interfaces (GUIs) are being increasingly used in the classroom to provide users of computer simulations with a friendly and visual approach to specifying all input parameters and increased configuration flexibility. In this study, the authors first describe a number of software and language options that are available to build GUIs. Subsequently, a comprehensive comparative assessment of possible alternatives is undertaken in the light of a benchmark educational program used in a course on computational fluid dynamics (CFD) at the University of Michigan. For the GUIs presented, their educational value with respect to flexible data entry and post-processing of results has been demonstrated. In addition, the authors offer recommendations for pros and cons of available options in terms of platform independence, ease of programming, facilitation of interaction with students, and flexibility. © 2005 Wiley Periodicals, Inc. Comput Appl Eng Educ 13: 48,59, 2005; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20029 [source] Early Surgical Morbidity and Mortality in Adults with Congenital Heart Disease: The University of Michigan ExperienceCONGENITAL HEART DISEASE, Issue 2 2008Ginnie L. Abarbanell MD ABSTRACT Objectives., To review early surgical outcomes in a contemporary series of adults with congenital heart disease (CHD) undergoing cardiac operations at the University of Michigan, and to investigate possible preoperative and intraoperative risk factors for morbidity and mortality. Methods., A retrospective medical record review was performed for all patients ,18 years of age who underwent open heart operations by a pediatric cardiothoracic surgeon at the University of Michigan Congenital Heart Center between January 1, 1998 and December 31, 2004. Records from a cohort of pediatric patients ages 1,17 years were matched to a subset of the adult patients by surgical procedure and date of operation. Results., In total, 243 cardiac surgical operations were performed in 234 adult patients with CHD. Overall mortality was 4.7% (11/234). The incidence of major postoperative complications was 10% (23/234) with a 19% (45/23) minor complication rate. The most common postoperative complication was atrial arrhythmias in 10.8% (25/234). The presence of preoperative lung or liver disease, prolonged cardiopulmonary bypass and aortic cross clamp times, and postoperative elevated inotropic score and serum lactates were significant predictors of mortality in adults. There was no difference between the adult and pediatric cohorts in terms of mortality and morbidity. Conclusions., The postoperative course in adults following surgery for CHD is generally uncomplicated and early survival should be expected. Certain risk factors for increased mortality in this patient population may include preoperative presence of chronic lung or liver dysfunction, prolonged cardiopulmonary bypass and aortic cross-clamp times, and postoperative elevated inotropic score and serum lactate levels. [source] Susceptibility of a Northern Hardwood Forest to Exotic Earthworm InvasionCONSERVATION BIOLOGY, Issue 4 2005MICHAEL J. GUNDALE Acer saccharum; Bosque Nacional Ottawa; lombrices invasoras; Sylvania Wilderness Area; uso del suelo Abstract:,Numerous exotic earthworm species are colonizing northern hardwood forests of North America, where no native earthworms exist. Upon invasion, earthworms have been shown to alter the surface soil environment and plant populations and communities. We sought to identify land-use factors in the Ottawa National Forest (ONF), Michigan (U.S.A.), that contribute to earthworm invasion in forest dominated by sugar maple (Acer saccharum Marsh.) so that the susceptibility to additional colonization could be evaluated. We sampled earthworm communities in Sylvania Wilderness Area, a unique old-growth hardwood forest, and nonwilderness sites influenced by recreational fishing, recent timber harvesting, or roads. All the nonwilderness sites contained one to five species of exotic earthworms. In contrast, only 50% of wilderness sites contained exotic earthworms, all of a single species. Nonwilderness sites also had thinner litter and duff layers, higher soil C and N content, and higher nitrogen mineralization potentials than Sylvania sites. Two central differences between Sylvania and nonwilderness sites were that all nonwilderness sites were in close contact with roads and had a history of timber harvest, whereas these factors were not present in Sylvania Wilderness Area. Using average rates of colonization, we constructed two geographic information system models to estimate the percentage of sugar maple on the ONF falling within a theoretical 100-year invasion distance of roads and of second-growth sugar maple as relative indices of susceptibility to invasion. Both models indicated high susceptibility to invasion, with 91.7% and 98.9% of sugar maple habitat falling within a theoretical 100-year invasion distance of roads or historical harvests, respectively. Resumen:,Numerosas especies de lombrices exóticas están colonizando los bosques boreales, en los que previamente no existían lombrices terrestres nativas. Por encima de la invasión, se ha demostrado que las lombrices alteran el ambiente superficial del suelo, así como a las comunidades y poblaciones de plantas. Tratamos de identificar factores de uso del suelo en el Bosque Nacional Ottawa (BNO), Michigan, E. U. A., que contribuyen a la invasión de lombrices en bosques dominados por arces (Acer saccharum Marsh.), para poder evaluar la susceptibilidad a futuras invasiones. Muestreamos comunidades de lombrices en Sylvania Wilderness Area, un bosque maduro único, y en sitios no silvestres influenciados por pesca deportiva, cosecha reciente de madera o caminos. Todas las áreas no silvestres contenían 1 - 5 especies de lombrices exóticas. En contraste, solo 50% de los sitios silvestres contenían lombrices exóticas, todas de una sola especie. Los sitios no silvestres también tenían capas de hojarasca y de mantillo más delgadas, mayor contenido de C y N del suelo y mayor potencial de mineralización del nitrógeno que los sitios en Sylvania. Dos diferencias centrales entre Sylvania y los sitios no silvestres fueron que estos estaban en contacto cercano con caminos y tenían una historia de cosecha de madera, mientras que estos factores no estuvieron presentes en Sylvania Wilderness Area. Utilizando tasas promedio de colonización, construimos dos modelos de sistemas de información geográfica para estimar el porcentaje de arces en el BNO que queda a una distancia teórica de invasión en 100 años; con caminos y arce de crecimiento secundario como índices relativos de susceptibilidad a la invasión. Ambos modelos indicaron alta susceptibilidad a la invasión, con 91.7% y 98.9% del hábitat de arce dentro de la distancia teórica de invasión en 100 años o con cosechas históricas, respectivamente. [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] The role of Late Holocene climate variability in the expansion of yellow birch in the western Great Lakes regionDIVERSITY AND DISTRIBUTIONS, Issue 5 2002Stephen T. Jackson Abstract. Pollen records from the western Great Lakes region of North America show substantial increases in birch pollen percentages during the late Holocene. The vegetational and population dynamics underlying the birch increase have received little attention, in part because of the inability to discriminate among species of birch based on pollen morphology. We used analyses of pollen and plant macrofossils from four lakes in the Upper Peninsula of Michigan to document that the birch pollen increase represents a regional expansion of yellow birch (Betula alleghaniensis) populations, which was initiated c. 4500 years ago. Whether yellow birch invaded the region at this time or simply expanded from small, previously established populations is not clear, although it probably did not grow near our study sites before the expansion. The initial expansion occurred during an independently documented period of high moisture and high water levels in Lake Michigan. A subsequent expansion in yellow birch abundance and distribution occurred c. 3000 years ago, coinciding with a second period of increased moisture and high lake-levels. The yellow birch expansion may have been modulated by millennial-scale climate variability, with most rapid expansion occurring during relatively wet periods. [source] Geomorphic and riparian forest influences on characteristics of large wood and large-wood jams in old-growth and second-growth forests in Northern Michigan, USAEARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2007Arthur E. L. Morris Abstract Large wood (LW; pieces with diameter greater than 10 cm and length greater than 1 m) and large-wood jams (LWJs; two or more pieces of LW in contact with each other) are important components of stream ecosystems that are often distributed along stream channels in response to geomorphic and riparian forest factors that interact hierarchically. As a result, information on these relationships is valuable for predicting patterns of wood accumulation and characteristics of individual pieces of wood. We studied relationships between geomorphic and riparian factors and LW and LWJ structure in different geomorphic settings associated with old-growth and second-growth settings in Upper Michigan. We used redundancy analysis (RDA) and regression tree analysis to evaluate changes in LW and LWJ structural characteristics among geomorphic and riparian forest settings. Geomorphic factors explained 38·5% of the variability in LW and LWJ characteristics, riparian forest factors uniquely explained 18·4% of the variance and the intersection of the two categories of environmental factors (i.e. the redundant portion) was 29·8%. At the landscape scale, our multivariate analyses suggest that the presence of rock-plane bedding was an important predictor of the number of LWJs and the percent of channel spanned by LWJs. Our analyses suggest differences in relationships between geomorphic factors and LW and LWJ structure. Channel width, distance from headwaters, gradient and sinuosity were identified by regression tree analyses as the most important variables for predicting LW characteristics, while channel width and confinement were the most important variables for predicting LWJ characteristics. Old-growth settings generally contained a higher proportion of conifer and LW (both in and out of LWJs) with greater diameter and volume than in second-growth settings. Our study supports the view that restoration of wood to streams will benefit from considering the associations of wood structure with landscape and reach-scale geomorphology. Copyright © 2007 John Wiley & Sons, Ltd. [source] Exposure and effects assessment of resident mink (Mustela vison) exposed to polychlorinated dibenzofurans and other dioxin-like compounds in the Tittabawassee River basin, Midland, Michigan, USA,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2008Matthew J. Zwiernik Abstract Historically, sediments and floodplain soils of the Tittabawassee River (TR; MI, USA) have been contaminated with polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo- p -dioxins (PCDDs), and polychlorinatedbiphenyls (PCBs). Median concentrations of 2,3,7,8-tetrachlorodibenzo- p -dioxin equivalents (TEQs) based on 2006 World Health Organization tetrachloro-dibenzo- p -dioxin toxic equivalency factors (TEFs) in the diet of mink (Mustela vison) ranged from 6.8 × 10,1 ng TEQ/kg wet weight upstream of the primary source of PCDF to 3.1 × 101 ng TEQ/kg wet weight downstream. Estimates of toxicity reference values (TRVs) derived from laboratory studies with individual PCDDs/PCDFs and PCB congeners or mixtures of those congeners, as well as application of TEFs, were compared to site-specific measures of mink exposure. Hazard quotients based on exposures expressed as concentrations of TEQs in the 95th percentile of the mink diet or liver and the no-observable-adverse-effect TRVs were determined to be 1.7 and 8.6, respectively. The resident mink survey, however, including number of mink present, morphological measures, sex ratios, population age structure, and gross and histological tissue examination, indicated no observable adverse effects. This resulted for multiple reasons: First, the exposure estimate was conservative, and second, the predominantly PCDF congener mixture present in the TR appeared to be less potent than predicted from TEQs based on dose,response comparisons. Given this, there appears to be great uncertainty in comparing the measured concentrations of TEQs at this site to TRVs derived from different congeners or congener mixtures. Based on the lack of negative outcomes for any measurement endpoints examined, including jaw lesions, a sentinel indicator of possible adverse effects, and direct measures of effects on individual mink and their population, it was concluded that current concentrations of PCDDs/PCDFs were not causing adverse effects on resident mink of the TR. [source] Chemical amplification in an invaded food web: Seasonality and ontogeny in a high-biomass, low-diversity ecosystem,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2008Carla A. Ng Abstract The global spread of invasive species is changing the structure of aquatic food webs worldwide. The North American Great Lakes have proved particularly vulnerable to this threat. In nearshore areas, invasive benthic species such as dreissenid mussels and round gobies (Neogobius melanostomus) have gained dominance in recent years. Such species are driving the flow of energy and material from the water column to the benthic zone, with dramatic effect on nutrient and contaminant cycling. Here, we develop a stage-structured model of a benthified food web in Lake Michigan with seasonal resolution and show how its bioaccumulation patterns differ from expected ones. Our model suggests that contaminant recycling through the consumption of lipid-rich fish eggs and mussel detritus is responsible for these differences. In southern Lake Michigan's Calumet Harbor (Chicago, IL, USA), round gobies have nitrogen isotope signatures with considerable spread, with some values higher than their predators and others lower than their prey. Contrary to patterns observed in linear pelagic systems, we predict that polychlorinated biphenyl (PCB) concentrations in these fish decrease with increasing size due to the lipid- and benthos-enriched diets of smaller fish. We also present here round goby PCB concentrations measured in 2005 after an invasional succession in Calumet Harbor and demonstrate how the change from one invasive mussel species to another may have led to a decrease in round goby PCB accumulation. Our results suggest that benthic-dominated systems differ from pelagic ones chiefly due to the influence of detritus and that these effects are exacerbated in systems with low species diversity and high biomass. [source] Water-column concentrations and partitioning of polybrominated diphenyl ethers in the New York/New Jersey Harbor, USAENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2008Archil Zarnadze Abstract Despite the emerging concern regarding polybrominated diphenyl ethers (BDEs), very few measurements of BDE concentrations in ambient water have been published. In the present study, BDEs were measured in water samples from the New York/New Jersey Harbor (USA). Samples were taken in Raritan Bay west of Sandy Hook during four intensive sampling campaigns in 2000 and 2001. Congeners 17, 47, 99, 100, 153, 154, 183, and 209 were detected. Total BDE (,BDE) concentrations (average ± standard deviation) were 175 ± 75 ng/g in the particle phase and 110 ± 72 pg/L in the apparent dissolved phase. The deca-congener, BDE 209, constituted 85 and 9% of ,BDEs in the particle and apparent dissolved phases, respectively. The ,BDE levels are significantly higher than those measured in Lake Ontario, USA, and in The Netherlands, but they are similar to concentrations measured in Lake Michigan and San Francisco Bay (both USA). Calculated values of the organic carbon-water partition coefficient (KOC) were strongly correlated with literature values of the octanol-water partition coefficient (KOW). The data suggest that sorption of BDEs to colloids is important in this system, although quantifying the extent of colloid sorption is difficult. [source] Evaluating polycyclic aromatic hydrocarbons using a yeast bioassayENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2007Abeer Alnafisi Abstract Sixteen polycyclic aromatic hydrocarbons (PAHs) were evaluated for the ability to activate aryl hydrocarbon (Ah) receptor signaling in a yeast-based bioassay. Individual PAHs were classified as inactive or as weakly, moderately, or strongly active based on induction of human Ah receptor signaling. Indeno[1,2,3- cd]pyrene, chrysene, benzo[a]anthracene, benzo[a]pyrene, benzo[j]fluoranthene, and benzo[k]fluoranthene were the most potent activators of human Ah receptor signaling. Various mixtures of PAHs had additive or synergistic effects in the bioassay. Environmental samples from the New Orleans (Louisiana, USA) and Detroit (Michigan, USA) areas that were previously analyzed for PAH composition and quantity were tested in this bioassay. Weak but statistically significant relationships were found when the analytically measured levels of PAHs were correlated with sample dilutions that gave 25% effective concentration signaling levels in the Ah receptor assay. We conclude that this Ah receptor signaling assay may be useful for preliminary biomonitoring of samples for PAHs and other Ah receptor ligands. [source] Slow desorption behavior of one highly resistant aromatic amine in Lake Macatawa, Michigan, USA, sedimentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2005Shihua Chen Abstract The desorption behavior of benzidine from Lake Macatawa (Holland, MI, USA) sediment was investigated in this study using batch solvent extraction method. Seven solvents were tested as the extracting reagents: Deionized water (DI), calcium chloride in DI (CaCl2), sodium hydroxide in DI (NaOH), acetonitrile (ACN), a mixture of acetonitrile and ammonium acetate in DI (ACNNH4OAc), methanol (MeOH), and hydrochloric acid in DI (HCl). These solvents are proposed to react with sediment-associated benzidine by different mechanisms (e.g., cation exchange, hydrophobic partitioning, and covalent binding). Three sets of sorption isotherm experiments were conducted separately in these seven solvents with a 7-d, three-week, and two-month contact time. The results demonstrated nonlinear isotherms with Freundlich 1/n values varying from 0.25 to 0.52. The desorption behavior of benzidine in the solvents was evaluated after the sorption of benzidine onto the sediment with same contact times of 7 d, three weeks, and two months. A two-stage model subsequently was applied to simulate the experimental data. The rapidly desorbing rate constants were on the order of one to two per day for ACN, ACN-NH4OAc, and NaOH solvents, and the slowly desorbing rate constants were on the order of 10,5 to 10,4/d. Sequential desorption experiment demonstrated low total extraction efficiency of less than 40%. Both the observed sorption and desorption phenomena suggested that hysteresis and/or mass-transfer limited diffusion may result in the slow desorption behavior observed in this study. [source] Complete elimination of carbonates: A critical step in the accurate measurement of organic and black carbon in sedimentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005Marta T. Lukasewycz Abstract Accurate measurement of organic carbon (OC) and black carbon (BC) in sediments requires the complete removal of coexisting inorganic carbonates from the sample before instrumental analysis. The removal of carbonates from sediments is achieved with acidification, which causes the dissolution and decomposition of carbonates with accompanying effervescence. This effervescence, or the lack of it, is commonly used as an indicator for the presence or absence of carbonates. We have found that the lack of effervescence endpoint used with the direct acidification method (adding aliquots of acid to samples) is not a reliable indicator for complete removal of carbonates from sediment samples. The ineffectiveness of the lack of effervescence endpoint, we believe, is caused by the presence of carbonates with dissolution rates much slower than those of calcite, resulting in much slower rates of visible effervescence. We propose and demonstrate a method for determining the amount of acid required for complete elimination of all carbonates using Lake Michigan (USA) sediment samples. Based on our experiences with the lack of effervescence endpoint, we recommend that in any scheme for analysis of OC and/or BC, a minimum of two samples be treated with three different levels of acidification, with the lowest level being the same as that planned for all the OC and/or BC analyses. There can be no significant differences among the OC and BC contents measured using the three different levels of acidification. [source] Space,time modeling of 20 years of daily air temperature in the Chicago metropolitan regionENVIRONMETRICS, Issue 5 2009Hae-Kyung Im Abstract We analyze 20 years of daily minimum and maximum air temperature data in the Chicago metropolitan region and propose a parsimonious model that describes their mean function and the space,time covariance structure. The mean function contains a long-term trend, annual and semiannual harmonics, and physical covariates such as latitude, distance to the Lake Michigan, and winds, each interacted with the harmonic terms, thus allowing the effects of physical covariates to vary smoothly over time. The temporal correlation at a given location is described using an ARMA(1,2) model. The residuals (innovations) from this models are treated as independent replications of a spatial process with covariance structure in the Matérn class. The space,time covariance structure parameters are allowed to vary seasonally. Using the estimated covariance structure, we interpolate the temperature to a fine grid in the Chicago metropolitan region. This procedure borrows information from temporally and spatially adjacent data. The methods presented in this paper should be useful to approach other environmental problems where the data are discrete and regular in time but irregular in space. Copyright © 2008 John Wiley & Sons, Ltd. [source] Airway inflammation in Michigan pleasure horses: prevalence and risk factorsEQUINE VETERINARY JOURNAL, Issue 4 2006N. E. Robinson Summary Reasons for performing study: Although subclinical airway inflammation is thought to be common in horses, there is little information on its prevalence and none on risk factors. Objective: To determine the prevalence and risk factors for an increased number of inflammatory cells and for mucus accumulation in the trachea of pleasure horses. Methods: Horses (n = 266) in stables (n = 21) in Michigan were examined endoscopically, once in winter and once in summer 2004. Visible tracheal mucoid secretions were graded 0,5 and inflammatory cell numbers counted in a tracheal lavage sample. Information collected about each horse included age, gender, presence of cough, percent time indoors and source of roughage. The repeated measures were analysed by generalised estimating equations and linear mixed models. Results: Horses eating hay, especially from round bales, had the most neutrophils, whereas horses feeding from pasture had the fewest. Being female and being outdoors in winter were associated with increased numbers of inflammatory cells. Older horses had fewer macrophages than young horses. More than 70% of horses had >20% neutrophils in tracheal lavage. Twenty percent of horses had a mucus accumulation score >1; 17% had both a mucus score >1 and >20% neutrophils. The significant risk factors for mucus accumulation >1 were age >15 years, feeding on hay as compared to pasture, and being outdoors for more than 80% time in winter. Even though mucus accumulation score >1 was a risk factor for cough, only half of such horses coughed. Cough and mucus accumulation were associated with increased number of neutrophils. Conclusions: In comparison to pasture feeding, hay feeding, particularly from round bales, was associated with an increased number of neutrophils in the airway. Being outdoors in winter was associated with increased numbers of inflammatory cells and with mucus accumulation. Because 70% of horses have >20% neutrophils, this value should not be used as the sole indicator of airway inflammation. Potential relevance: The study reinforces the importance of hay feeding and older age as risk factors for inflammatory airway disease. Horses that do not have ,heaves' may be best kept indoors when winters are cold. [source] THE EVOLUTION OF SEXUAL SIZE DIMORPHISM IN THE HOUSE FINCH.EVOLUTION, Issue 6 2000Abstract Recent colonization of ecologically distinct areas in North America by the house finch (Carpodacus mexicanus) was accompanied by strong population divergence in sexual size dimorphism. Here we examined whether this divergence was produced by population differences in local selection pressures acting on each sex. In a long-term study of recently established populations in Alabama, Michigan, and Montana, we examined three selection episodes for each sex: selection for pairing success, overwinter survival, and within-season fecundity. Populations varied in intensity of these selection episodes, the contribution of each episode to the net selection, and in the targets of selection. Direction and intensity of selection strongly differed between sexes, and different selection episodes often favored opposite changes in morphological traits. In each population, current net selection for sexual dimorphism was highly concordant with observed sexual dimorphism,in each population, selection for dimorphism was the strongest on the most dimorphic traits. Strong directional selection on sexually dimorphic traits, and similar intensities of selection in both sexes, suggest that in each of the recently established populations, both males and females are far from their local fitness optimum, and that sexual dimorphism has arisen from adaptive responses in both sexes. Population differences in patterns of selection on dimorphism, combined with both low levels of ontogenetic integration in heritable sexually dimorphic traits and sexual dimorphism in growth patterns, may account for the close correspondence between dimorphism in selection and observed dimorphism in morphology across house finch populations. [source] Rapid evolution in crop-weed hybrids under artificial selection for divergent life historiesEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2009Lesley G. Campbell Abstract When species hybridize, offspring typically exhibit reduced fitness and maladapted phenotypes. This situation has biosafety implications regarding the unintended spread of novel transgenes, and risk assessments of crop-wild hybrids often assume that poorly adapted hybrid progeny will not evolve adaptive phenotypes. We explored the evolutionary potential of early generation hybrids using nontransgenic wild and cultivated radish (Raphanus raphanistrum, Raphanus sativus) as a model system. We imposed four generations of selection for two weedy traits , early flowering or large size , and measured responses in a common garden in Michigan, USA. Under selection for early flowering, hybrids evolved to flower as early as wild lineages, which changed little. These early-flowering hybrids also recovered wild-type pollen fertility, suggesting a genetic correlation that could accelerate the loss of crop traits when a short life cycle is advantageous. Under selection for large size at reproduction, hybrids evolved longer leaves faster than wild lineages, a potentially advantageous phenotype under longer growing seasons. Although early generation hybrid offspring have reduced fitness, our findings provide novel support for rapid adaptation in crop-wild hybrid populations. Biosafety risk assessment programs should consider the possibility of rapid evolution of weedy traits from early generations of seemingly unfit crop-wild hybrids. [source] Isolation of a Carnobacterium maltaromaticum- like bacterium from systemically infected lake whitefish (Coregonus clupeaformis)FEMS MICROBIOLOGY LETTERS, Issue 1 2008Thomas P. Loch Abstract Herein we report on the first isolation of a Carnobacterium maltaromaticum -like bacterium from kidneys and swim bladders of lake whitefish (Coregonus clupeaformis) caught from Lakes Michigan and Huron, Michigan. Isolates were Gram-positive, nonmotile, facultatively anaerobic, asporogenous rods that did not produce catalase, cytochrome oxidase, or H2S, and did not grow on acetate agar. Except for carbohydrate fermentation, many phenotypic characteristics of lake whitefish isolates coincided with those of C. maltaromaticum, the causative agent of pseudokidney disease. Partial sequencing of 16S and 23S rRNA genes, as well as the piscicolin 126 precursor gene, yielded 97% and 98% nucleotide matches with C. maltaromaticum, respectively (accession numbers EU546836 and EU546837; EU643471). Phylogenetic analyses showed that lake whitefish isolates of this study are highly related, yet not fully identical to C. maltaromaticum. The presence of the C. maltaromaticum -like bacterium was associated with splenomegaly, renal and splenic congestion, and thickening of the swim bladder wall with accumulation of a mucoid exudate. Examination of stained tissue sections revealed renal and splenic congestion, vacuolation and bile stasis within the liver, and hyperplasia within the epithelial lining of the swim bladder. The concurrent presence of pathological changes and the C. maltaromaticum -like bacteria suggests that this bacterium is pathogenic to lake whitefish. [source] PCR primers for identification of Sirococcus conigenus and S. tsugae, and detection of S. conigenus from symptomatic and asymptomatic red pine shootsFOREST PATHOLOGY, Issue 3 2008D. R. Smith Summary Regions of diversity in the internal transcribed spacer (ITS) sequences of Sirococcus species were exploited to design primer pairs used in a PCR-based method for the identification of the conifer shoot blight pathogen Sirococcus conigenus and the closely related fungus Sirococcus tsugae. The specificity of each primer pair for the respective fungus, detection limits and utility for detection from host material were confirmed. The S. conigenus primers were then used to detect this pathogen in tissues of symptomatic or apparently healthy red pine shoots collected at six locations in Wisconsin and Michigan and results compared with those obtained using a cultural assay. For needles, bark and wood of symptomatic shoots, the mean frequencies of detection of S. conigenus using the PCR-based methods were consistent (,7.5 out of 10) and always greater than for the cultural assay. Detection from symptomatic shoots using the cultural assay was more frequent from needles than from bark or wood. Both the PCR-based method and the cultural assay detected S. conigenus in similar frequencies from asymptomatic shoots, although less frequently than from symptomatic shoots. The efficiency of the PCR-based method and its utility for direct testing of host material should make it particularly useful in areas where multiple shoot blight pathogens are found. [source] Response of secondary production by macroinvertebrates to large wood addition in three Michigan streamsFRESHWATER BIOLOGY, Issue 8 2009SALLY A. ENTREKIN Summary 1.,We measured responses in macroinvertebrate secondary production after large wood additions to three forested headwater streams in the Upper Peninsula of Michigan. These streams had fine-grained sediments and low retention capacity due to low amounts of in-channel wood from a legacy of past logging. We predicted that wood addition would increase macroinvertebrate secondary production by increasing exposed coarse substrate and retention of organic matter. 2.,Large wood (25 logs) was added haphazardly to a 100-m reach in each stream, and a 100-m upstream reach served as control; each reach was sampled monthly, 1 year before and 2 years after wood addition (i.e. BACI design). Macroinvertebrate secondary production was measured 1 year after wood addition in two habitat types: inorganic sediments of the main channel and debris accumulations of leaf litter and small wood. 3.,Overall macroinvertebrate production did not change significantly because each stream responded differently to wood addition. Production increased by 22% in the main-channel of one stream, and showed insignificant changes in the other two streams compared to values before wood addition. Changes in main-channel macroinvertebrate production were related to small changes in substrate composition, which probably affected habitat and periphyton abundance. Macroinvertebrate production was much greater in debris accumulations than in the main-channel, indicating the potential for increased retention of leaf litter to increase overall macroinvertebrate production, especially in autumn. 4.,Surrounding land use, substrate composition, temperature and method of log placement are variables that interact to influence the response of stream biota to wood additions. In most studies, wood additions occur in altered catchments, are rarely monitored, and secondary production is not a common metric. Our results suggest that the time required for measurable changes in geomorphology, organic matter retention, or invertebrate production is likely to take years to achieve, so monitoring should span more than 5 years, and ecosystem metrics, such as macroinvertebrate secondary production, should be incorporated into restoration monitoring programs. [source] Transformation of the offshore benthic community in Lake Michigan: recent shift from the native amphipod Diporeia spp. to the invasive mussel Dreissena rostriformis bugensisFRESHWATER BIOLOGY, Issue 3 2009THOMAS F. NALEPA Summary 1. The native amphipod Diporeia spp. was once the dominant benthic organism in Lake Michigan and served as an important pathway of energy flow from lower to upper trophic levels. Lake-wide surveys were conducted in 1994/1995, 2000 and 2005, and abundances of Diporeia and the invasive bivalves Dreissena polymorpha (zebra mussel) and Dreissena rostriformis bugensis (quagga mussel) were assessed. In addition, more frequent surveys were conducted in the southern region of the lake between 1980 and 2007 to augment trend interpretation. 2. Between 1994/1995 and 2005, lake-wide density of Diporeia declined from 5365 to 329 m,2, and biomass (dry weight, DW) declined from 3.9 to 0.4 g DW m,2. The percentage of all sites with no Diporeia increased over time: 1.1% in 1994/1995, 21.7% in 2000 and 66.9% in 2005. On the other hand, total dreissenid density increased from 173 to 8816 m,2, and total biomass increased from 0.4 to 28.6 g DW m,2. Over this 10-year time period, D. r. bugensis displaced D. polymorpha as the dominant dreissenid, comprising 97.7% of the total population in 2005. In 2007, Diporeia was rarely found at depths shallower than 90 m and continued to decline at greater depths, whereas densities of D. r. bugensis continued to increase at depths greater than 50 m. 3. The decline in Diporeia occurred progressively from shallow to deep regions, and was temporally coincident with the expansion of D. polymorpha in nearshore waters followed by the expansion of D. r. bugensis in offshore waters. In addition, Diporeia density was negatively related to dreissenid density within and across depth intervals; the latter result indicated that dreissenids in shallow waters remotely influenced Diporeia in deep waters. 4. With the loss of Diporeia and increase in D. r. bugensis, the benthic community has become a major energy sink rather that a pathway to upper trophic levels. With this replacement of dominant taxa, we estimate that the relative benthic energy pool increased from 17 to 109 kcal m,2 between 1994/1995 and 2005, and to 342 kcal m,2 by 2007. We project that previously observed impacts on fish populations will continue and become more pronounced as the D. r. bugensis population continues to expand in deeper waters. [source] Benthic organic carbon influences denitrification in streams with high nitrate concentrationFRESHWATER BIOLOGY, Issue 7 2007CLAY P. ARANGO Summary 1. Anthropogenic activities have increased reactive nitrogen availability, and now many streams carry large nitrate loads to coastal ecosystems. Denitrification is potentially an important nitrogen sink, but few studies have investigated the influence of benthic organic carbon on denitrification in nitrate-rich streams. 2. Using the acetylene-block assay, we measured denitrification rates associated with benthic substrata having different proportions of organic matter in agricultural streams in two states in the mid-west of the U.S.A., Illinois and Michigan. 3. In Illinois, benthic organic matter varied little between seasons (5.9,7.0% of stream sediment), but nitrate concentrations were high in summer (>10 mg N L,1) and low (<0.5 mg N L,1) in autumn. Across all seasons and streams, the rate of denitrification ranged from 0.01 to 4.77 ,g N g,1 DM h,1 and was positively related to stream-water nitrate concentration. Within each stream, denitrification was positively related to benthic organic matter only when nitrate concentration exceeded published half-saturation constants. 4. In Michigan, streams had high nitrate concentrations and diverse benthic substrata which varied from 0.7 to 72.7% organic matter. Denitrification rate ranged from 0.12 to 11.06 ,g N g,1 DM h,1 and was positively related to the proportion of organic matter in each substratum. 5. Taken together, these results indicate that benthic organic carbon may play an important role in stream nitrogen cycling by stimulating denitrification when nitrate concentrations are high. [source] Diel interactions between prey behaviour and feeding in an invasive fish, the round goby, in a North American riverFRESHWATER BIOLOGY, Issue 4 2006STEPHANIE M. CARMAN Summary 1. We studied the diet of the invasive round goby (Neogobius melanostomus) on a diel basis in the Flint River, a warmwater stream in Michigan, U.S.A. Diet and available prey samples were collected seven times over a 24 h period in four consecutive months. The section of river studied lacked zebra mussels (Dreissena polymorpha), the primary prey of adult round gobies elsewhere in the Great Lakes region. 2. Diet changed on a diel basis with hydropsychid caddisfly and chironomid larvae predominating during the day, chironomid pupae dominating in the evening and heptageniid mayflies dominating at night. Simultaneous study of macroinvertebrate drift suggested that caddisfly and chironomid larvae were most likely picked from submerged rocks, chironomid pupae were most likely taken during their emergent ascent and mayflies were either captured from the drift or picked from rocks. 3. The Flint River lacks a diverse darter (Family: Percidae) and sculpin (Family: Cottidae) fauna and it appears that the round goby has occupied a generalised darter/sculpin niche. Our results indicate that round gobies have the potential to invade successfully riverine systems, particularly those lacking a diverse benthic fish assemblage. [source] Taxonomic and regional patterns in benthic macroinvertebrate elemental composition in streamsFRESHWATER BIOLOGY, Issue 11 2005MICHELLE A. EVANS-WHITE Summary 1. Ecological stoichiometry has been used to better understand dynamics in consumer growth and the role of consumer-recycled nutrients because it focuses on more than one element. Most research has focused on pelagic rather than benthic consumers. Variation in elemental composition among benthic consumer taxa would suggest that taxa differ in their susceptibility to nutrient limitation or in their role in recycling nutrients. 2. We collected benthic macroinvertebrates from streams in two regions (Indiana,Michigan and Wisconsin, U.S.A.) to examine taxonomic and regional variation in benthic macroinvertebrate body carbon (C), nitrogen (N), and phosphorus (P) concentrations and ratios. 3. Elemental composition varied little within taxa common to both regions. In contrast, elemental composition differed greatly among taxa and appeared to be related to phylogeny. The elemental composition of macroinvertebrates clustered into three distinct groups: insects, mollusks, and crustaceans. To a lesser extent, insects and mollusks also differed in elemental composition among genera. 4. Functional feeding groups (FFGs) differed in elemental composition, with predators having a higher N content than other groups. Substantial elemental imbalances between C and N were found between most primary consumers and their likely food sources, and the magnitude of the imbalance depended in part on the FFG. 5. Our results support an assumption of most ecological stoichiometry models that, within a species, the elemental composition of aquatic invertebrates is relatively constant. Variation in elemental composition among taxa at various higher taxonomic levels suggests that susceptibility of stream invertebrates to nutrient limitation and their role in nutrient cycling will strongly depend on phylogeny. [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] Soil carbon fluxes and stocks in a Great Lakes forest chronosequenceGLOBAL CHANGE BIOLOGY, Issue 1 2009JIANWU TANG Abstract We measured soil respiration and soil carbon stocks, as well as micrometeorological variables in a chronosequence of deciduous forests in Wisconsin and Michigan. The chronosequence consisted of (1) four recently disturbed stands, including a clearcut and repeatedly burned stand (burn), a blowdown and partial salvage stand (blowdown), a clearcut with sparse residual overstory (residual), and a regenerated stand from a complete clearcut (regenerated); (2) four young aspen (Populus tremuloides) stands in average age of 10 years; (3) four intermediate aspen stands in average age of 26 years; (4) four mature northern hardwood stands in average age of 73 years; and (5) an old-growth stand approximately 350-years old. We fitted site-based models and used continuous measurements of soil temperature to estimate cumulative soil respiration for the growing season of 2005 (days 133,295). Cumulative soil respiration in the growing season was estimated to be 513, 680, 747, 747, 794, 802, 690, and 571 g C m,2 in the burn, blowdown, residual, regenerated, young, intermediate, mature, and old-growth stands, respectively. The measured apparent temperature sensitivity of soil respiration was the highest in the regenerated stand, and declined from the young stands to the old-growth. Both, cumulative soil respiration and basal soil respiration at 10 °C, increased during stand establishment, peaked at intermediate age, and then decreased with age. Total soil carbon at 0,60 cm initially decreased after harvest, and increased after stands established. The old-growth stand accumulated carbon in deep layers of soils, but not in the surface soils. Our study suggests a complexity of long-term soil carbon dynamics, both in vertical depth and temporal scale. [source] Threshold citation analysis of influential articles, journals, institutions and researchers in accountingACCOUNTING & FINANCE, Issue 1 2009Kam C. Chan M40; M41 Abstract We use a threshold citation approach to measure the influence of articles, journals, institutions and researchers in accounting research. The Journal of Accounting Research, the Journal of Accounting and Economics and Accounting Review are the 3 most influential journals in accounting research. The 3 most influential institutions in accounting research are the University of Chicago, the University of Pennsylvania and the University of Michigan, while the 3 most frequently cited authors in accounting research are Richard G. Sloan, Robert E. Verrecchia and Paul M. Healy. [source] Michigan Basin Regional Ground Water Flow Discharge to Three Great LakesGROUND WATER, Issue 4 2002John Robert Hoaglund III Ground water discharge to the Great Lakes around the Lower Peninsula of Michigan is primarily from recharge in riparian basins and proximal upland areas that are especially important to the northern half of the Lake Michigan shoreline. A steady-state finite-difference model was developed to simulate ground water flow in four regional aquifers in Michigan's Lower Peninsula: the Glaciofluvial, Saginaw, Parma-Bayport, and Marshall aquifers interlayered with the Till/"red beds," Saginaw, and Michigan confining units, respectively. The model domain was laterally bound by a continuous specified-head boundary, formed from lakes Michigan, Huron, St. Clair, and Erie, with the St. Clair and Detroit River connecting channels. The model was developed to quantify regional ground water flow in the aquifer systems using independently determined recharge estimates. According to the flow model, local stream stages and discharges account for 95% of the overall model water budget; only 5% enters the lakes directly from the ground water system. Direct ground water discharge to the Great Lakes' shorelines was calculated at 36 m3/sec, accounting for 5% of the overall model water budget. Lowland areas contribute far less ground water discharge to the Great Lakes than upland areas. The model indicates that Saginaw Bay receives only ,1.13 m3/sec ground water; the southern half of the Lake Michigan shoreline receives only ,2.83 m3/sec. In contrast, the northern half of the Lake Michigan shoreline receives more than 17 m3/sec from upland areas. [source] Cost savings in migraine associated with less chest pain on new triptan therapy.HEADACHE, Issue 3 2003JT Wang Am J Manag Care. 2002 Feb;8(3 Suppl):S102-S107 Objectives: This article constructs an economic model to estimate cost of chest-pain-related care in migraine patients receiving almotriptan 12.5 mg compared with those receiving sumatriptan 50 mg. Study Design: This population-based, retrospective cohort study used data from the MEDSTAT Marketscan database (Ann Arbor, Michigan) to quantify incidence and costs of chest-pain-related diagnoses and procedures. After a 6-month exclusion period, the study used a pre-post design, with baseline and treatment periods defined, respectively, as 5 months before and after receiving sumatriptan therapy. An economic model was constructed to estimate annual cost savings per 1,000 patients receiving almotriptan instead of sumatriptan as a function of differing rates of chest pain. Annual direct medical cost avoided was calculated for a hypothetical health plan covering 1 million lives. Results: Among a cohort of 1,390 patients, the incidence of chest-pain-related diagnoses increased significantly (43.6%) with sumatriptan, from 110 during the baseline period to 158 during the treatment period (P = .003). Aggregate costs for chest-pain-related diagnoses and procedures increased 33.1%, from $22,713 to $30,234. Payments for inpatient hospital services rose 10-fold; costs for primary care visits and outpatient hospital visits rose 53.1% and 14.4%, respectively. Payments for angiography increased from $0 to $462, and costs for chest radiographs and electrocardiograms increased 58.7% and 31.2%, respectively. Sumatriptan treatment was associated with a 3-fold increase in payments for services for painful respiration and other chest pain. The model predicted $11,215 in direct medical cost savings annually per 1000 patients treated with almotriptan instead of sumatriptan. Annual direct medical costs avoided for the health plan totaled $195,913. Conclusion: Using almotriptan instead of sumatriptan will likely reduce the cost of chest-pain-related care for patients with migraine headaches. Comment: In my view, this study takes conjecture a step too far. The lower reported chest adverse events (AEs) reported in clinical trials where all AEs are scrutinized will not necessarily lead to lower reporting in the clinic. This hypothesis remains to be proven in a well-designed post-marketing surveillance program, untarnished by commercial sponsorship. Until such an independent prospective study is carried out, the extrapolations described here and in similar papers are pure conjecture and should be classed as the lowest grade of evidence on a par with uncorroborated clinical opinion. DSM [source] Neonatal health care costs related to smoking during pregnancyHEALTH ECONOMICS, Issue 3 2002E. Kathleen Adams Abstract Research objective: Much of the work on estimating health care costs attributable to smoking has failed to capture the effects and related costs of smoking during pregnancy. The goal of this study is to use data on smoking behavior, birth outcomes and resource utilization to estimate neonatal costs attributable to maternal smoking during pregnancy. Study design: We use 1995 data from the Center for Disease Control's (CDC) Pregnancy Risk Assessment Monitoring System (PRAMS) database. The PRAMS collects representative samples of births from 13 states (Alabama, Alaska, California, Florida, Georgia, Indiana, Maine, Michigan, New York (excluding New York City), Oklahoma, South Carolina, Washington, and West Virginia), and the District of Columbia. The 1995 PRAMS sample is approximately 25 000. Multivariate analysis is used to estimate the relationship of smoking to probability of admission to an NICU and, separately, the length of stay for those admitted or not admitted to an NICU. Neonatal costs are predicted for infants ,as is' and ,as if' their mother did not smoke. The difference between these constitutes smoking attributable neonatal costs; this divided by total neonatal costs constitutes the smoking attributable fraction (SAF). We use data from the MarketScanÔ database of the MedStatÔ Corporation to attach average dollar amounts to NICU and non-NICU nursery nights and data from the 1997 birth certificates to extrapolate the SAFs and attributable expenses to all states. Principal findings: The analysis showed that maternal smoking increased the relative risk of admission to an NICU by almost 20%. For infants admitted to the NICU, maternal smoking increased length of stay while for non- NICU infants it appeared to lower it. Over all births, however, smoking increased infant length of stay by 1.1%. NICU infants cost $2496 per night while in the NICU and $1796 while in a regular nursery compared to only $748 for non-NICU infants. The combination of the increased NICU use, longer stays and higher costs result in a positive smoking attributable fraction (SAF) for neonatal costs. The SAF across all states is 2.2%. Across the states, the SAF varied from a low of 1.3% in Texas to a high of 4.6% in Indiana. Conclusions: These results further confirm the adverse effects of smoking. Among mothers who smoke, smoking adds over $700 in neonatal costs. The smoking attributable neonatal costs in the US represent almost $367 million in 1996 dollars; these costs vary from less than a million in smaller states to over $35 million in California. These costs are highly preventable since the adverse effects of maternal smoking occur in the short-run and can be avoided by even a temporary cessation of maternal smoking. These cost estimates can be used by managed care plans, state and local public health officials and others to evaluate alternative smoking cessation programs. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||