Coral Terrace, FL, United States
Coral Terrace, FL, United States

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Kennedy V.S.,University of Cambridge | Breitburg D.L.,Smithsonian Environmental Research Center | Christman M.C.,MCC Statistical Consulting LLC | Luckenbach M.W.,Virginia Institute of Marine Science | And 7 more authors.
Journal of Shellfish Research | Year: 2011

A century-long decline of the fishery for the Eastern oyster Crassostrea virginica (Gmelin, 1791) in Maryland and Virginia stimulated numerous efforts by federal, state, and nongovernmental agencies to restore oyster populations, with limited success. To learn from recent efforts, we analyzed records of restoration and monitoring activities undertaken between 1990 and 2007 by 12 such agencies. Of the 1,037 oyster bars (reefs, beds, or grounds) for which we obtained data, 43% experienced both restoration and monitoring, with the remaining experiencing either restoration or monitoring only. Restoration activities involved adding substrate (shell), transplanting hatchery or wild seed (juvenile oysters), bar cleaning, and bagless dredging. Of these, substrate addition and transplanting seed were common actions, with bar cleaning and bagless dredging relatively uncommon. Limited monitoring efforts, a lack of replicated postrestoration sampling, and the effects of harvest on some restored bars hinders evaluations of the effectiveness of restoration activities. Future restoration activities should have clearly articulated objectives and be coordinated among agencies and across bars, which should also be off limits to fishing. To evaluate restoration efforts, experimental designs should include replication, quantitative sampling, and robust sample sizes, supplemented by pre-and postrestoration monitoring.


Christman M.C.,University of Florida | Christman M.C.,MCC Statistical Consulting LLC | Doctor D.H.,U.S. Geological Survey | Niemiller M.L.,University of Illinois at Urbana - Champaign | And 4 more authors.
PLoS ONE | Year: 2016

One of the most challenging fauna to study in situ is the obligate cave fauna because of the difficulty of sampling. Cave-limited species display patchy and restricted distributions, but it is often unclear whether the observed distribution is a sampling artifact or a true restriction in range. Further, the drivers of the distribution could be local environmental conditions, such as cave humidity, or they could be associated with surface features that are surrogates for cave conditions. If surface features can be used to predict the distribution of important cave taxa, then conservation management is more easily obtained. We examined the hypothesis that the presence of major faunal groups of cave obligate species could be predicted based on features of the earth surface. Georeferenced records of cave obligate amphipods, crayfish, fish, isopods, beetles, millipedes, pseudoscorpions, spiders, and springtails within the area of Appalachian Landscape Conservation Cooperative in the eastern United States (Illinois to Virginia and New York to Alabama) were assigned to 20 × 20 km grid cells. Habitat suitability for these faunal groups was modeled using logistic regression with twenty predictor variables within each grid cell, such as percent karst, soil features, temperature, precipitation, and elevation. Models successfully predicted the presence of a group greater than 65% of the time (mean = 88%) for the presence of single grid cell endemics, and for all faunal groups except pseudoscorpions. The most common predictor variables were latitude, percent karst, and the standard deviation of the Topographic Position Index (TPI), a measure of landscape rugosity within each grid cell. The overall success of these models points to a number of important connections between the surface and cave environments, and some of these, especially soil features and topographic variability, suggest new research directions. These models should prove to be useful tools in predicting the presence of species in understudied areas. © This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.


Hanifi A.,University of Florida | Culpepper T.,University of Florida | Mai V.,University of Florida | Anand A.,University of Florida | And 5 more authors.
Beneficial Microbes | Year: 2015

A probiotic formulation of Enterococcus faecium R0026 and Bacillus subtilis R0179 has been evaluated in previous clinical trials. However, B. subtilis R0179 has not been evaluated as a single probiotic strain or in combination with other strains at doses higher than 0.1×109 cfu. To establish oral dose-response tolerance and gastrointestinal (GI) viability of B. subtilis R0179, a randomised, double-blind, placebo-controlled trial in healthy adults (n=81; 18-50 years old) was conducted. Participants received B. subtilis R0179 at 0.1, 1.0 or 10×109 cfu/capsule/day or placebo for four weeks. General wellness was assessed using a daily questionnaire evaluating GI, cephalic, ear-nose-throat, behavioural, emetic, and epidermal symptoms. GI symptoms were further evaluated using a weekly gastrointestinal symptom rating scale (GSRS). GI transit viability of B. subtilis R0179 was assessed by plating and microbiota analysis by 16S rRNA at baseline, week 4 of the intervention and washout. General wellness and GI function were not affected by oral consumption of B. subtilis R0179 at any dose. Daily questionnaire syndrome scores were not different from baseline and did not exceed a clinically significant score of 1. GSRS syndrome scores were not different from baseline and ranged from 1.1±0.1 to 1.9±0.2. Faecal viable counts of B. subtilis R0179 demonstrated a dose response: the placebo group (1.1±0.1 log10 cfu/g) differed from 0.1×109 (4.6±0.1 log10 cfu/g), 1×109 (5.6±0.1 log10 cfu/g) and 10×109 (6.4±0.1 log10 cfu/g) (P<0.0001). No significant changes in phyla were observed, but sequence reads binned to multiple operational taxonomic units matching closest to Ruminococci increased during probiotic supplementation. B. subtilis R0179 survives passage through the human GI tract and is well tolerated by healthy adults at intakes from 0.1 to 10×109 cfu/day. The trial has been registered at www.clinicaltrials.gov under NCT01802151. © 2014 Wageningen Academic Publishers.


Dahl W.J.,University of Florida | Ford A.L.,University of Florida | Coppola J.A.,University of Florida | Lopez D.,University of Florida | And 7 more authors.
Beneficial Microbes | Year: 2016

The aim of the studies was to determine the effects of calcium carbonate and calcium phosphate supplementation on faecal Lactobacillus spp., with and without a probiotic supplement, in healthy adults. Study 1 comprised of a randomised, double-blind, crossover design; participants (n=15) received 2 capsules/d of 250 mg elemental calcium as calcium carbonate (Ca1) and calcium phosphate (Ca2) each for 2-week periods, with 2-week baseline and washout periods. Study 2 was a randomised, double-blind, crossover design; participants (n=17) received 2 capsules/d of Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011 (probiotic) alone, the probiotic with 2 capsules/d of Ca1, and probiotic with 2 capsules/d of Ca2 each for 2-week periods with 2-week baseline and washout periods. In both studies, stools were collected during the baseline, intervention and washout periods for Lactobacillus spp. quantification and qPCR analyses. Participants completed daily questionnaires of stool frequency and compliance. In Study 1, neither calcium supplement influenced viable counts of resident Lactobacillus spp., genome equivalents of lactic acid bacteria or stool frequency. In Study 2, faecal Lactobacillus spp. counts were significantly enhanced from baseline when the probiotic was administered with Ca2 (4.83±0.30, 5.79±0.31) (P=0.02), but not with Ca1 (4.98±0.31) or with the probiotic alone (5.36±0.31, 5.55±0.29) (not significant). Detection of L. helveticus R0052 and L. rhamnosus R0011 was significantly increased with all treatments, but did not differ among treatments. There were no changes in weekly stool frequency. Calcium phosphate co-administration may increase gastrointestinal survival of orally-administered Lactobacillus spp. © 2015 Wageningen Academic Publishers.


PubMed | Sensus B.V., University of Florida, General Mills Bell Institute of Health and Nutrition and MCC Statistical Consulting LLC
Type: | Journal: Journal of nutritional science | Year: 2014

The impact of oligofructose (OF) intake on stool frequency has not been clearly substantiated, while significant gastrointestinal (GI) symptoms have been reported in some individuals. The aim of the present study was to determine the effects of OF on stool frequency and GI symptoms in healthy adults. In an 8-week, randomised, double-blind, parallel-arm study, ninety-eight participants were provided with 16g OF in yogurt and snack bars (twenty male and thirty female) or matching control foods (seventeen male and thirty-one female), to incorporate, by replacement, into their usual diets. Participants completed a daily online questionnaire recording stool frequency and rating four symptoms: bloating, flatulence, abdominal cramping and noise, each on a Likert scale from 0 for none (no symptoms) to 6 for very severe, with a maximum symptom intensity score of 24 (sum of severities from all four symptoms). Online 24h dietary recalls were completed during pre-baseline and weeks 4, 6 and 8 to determine fibre intake. When provided with OF foods, fibre intake increased to 243 (sem 05) g/d from pre-baseline (121 (sem 05) g/d; P<0001). Stool frequency increased with OF from 13 (sem 02) to 18 (sem 02) stools per d in males and 10 (sem 01) to 14 (sem 01) stools per d in females during intervention weeks compared with pre-baseline (P<005),but did not change for control participants (males: 16 (sem 02) to 18 (sem 02); females: 13 (sem 01) to 14 (sem 01)). Flatulence was the most commonly reported symptom. Mean GI symptom intensity score was higher for the OF group (32 (sem 03)) v. control (17 (sem 01)) (P<001), with few participants reporting above moderate symptoms. No change in symptom intensity occurred over time. Consuming yogurt and snack bars with 16g OF improves regularity in young healthy adults. However, GI symptoms, resulting from an increase in oligofructose intake, may not diminish with time.


Dahl W.J.,University of Florida | Ford A.L.,University of Florida | Ukhanova M.,University of Florida | Radford A.,University of Florida | And 3 more authors.
Journal of Functional Foods | Year: 2016

The effects of resistant potato starches on gastrointestinal (GI) function and microbiota in healthy individuals were investigated. In a 6-week, double-blind, cross-over study, subjects (N = 57; 21M; 36F) were randomised to consume 30 g fibre/d from one of three chemically modified potato starches (RS4-A, soluble, viscous; RS4-B, soluble, non-viscous; RS4-C, insoluble, non-viscous) and control in beverages for 2 weeks with a 1-week washout and daily reporting of stool frequency, Bristol Stool Form Scale (BSFS), GI symptoms and compliance. Faecal microbiota was analysed by qPCR and 16S rRNA sequencing. Stool frequency and BSFS increased only with RS4-B (P < 0.01). GI symptoms were minimal with slight increases in flatulence with all interventions (P < 0.001). There were no changes in Lactobacillus or Bifidobacteria spp. However, RS4-B decreased Firmicutes (P = 0.02) and the ratio of Firmicutes to Bacteroidetes (P = 0.01). Resistant potato starches vary in their effects on GI function, which may be related to shifts in intestinal microbiota. © 2016.


Langkamp-Henken B.,University of Florida | Rowe C.C.,University of Florida | Ford A.L.,University of Florida | Christman M.C.,University of Florida | And 7 more authors.
British Journal of Nutrition | Year: 2015

Acute psychological stress is positively associated with a cold/flu. The present randomised, double-blind, placebo-controlled study examined the effect of three potentially probiotic bacteria on the proportion of healthy days over a 6-week period in academically stressed undergraduate students (n 581) who received Lactobacillus helveticus R0052, Bifidobacterium longum ssp. infantis R0033, Bifidobacterium bifidum R0071 or placebo. On each day, participants recorded the intensity (scale: 0 = not experiencing to 3 = very intense) for nine cold/flu symptoms, and a sum of symptom intensity >6 was designated as a day of cold/flu. B. bifidum resulted in a greater proportion of healthy days than placebo (P≤0.05). The percentage of participants reporting ≥1 d of cold/flu during the 6-week intervention period was significantly lower with B. bifidum than with placebo (P<0.05). There were no effects of B. infantis or L. helveticus compared with placebo on either outcome. A predictive model accounted for influential characteristics and their interactions on daily reporting of cold/flu episodes. The proportion of participants reporting a cold on any given day was lower at weeks 2 and 3 with B. bifidum and B. infantis than with placebo for the average level of stress and the most commonly reported number of hours of sleep. Daily intake of bifidobacteria provides benefit related to cold/flu outcomes during acute stress. © The Authors 2015.


Borges S.L.,University of Maryland University College | Borges S.L.,U.S. Environmental Protection Agency | Vyas N.B.,U.S. Geological Survey | Christman M.C.,MCC Statistical Consulting LLC
Environmental Management | Year: 2014

Field studies of pesticide effects on birds often utilize indicator species with the purpose of extrapolating to other avian taxa. Little guidance exists for choosing indicator species to monitor the presence and/or effects of contaminants that are labile in the environment or body, but are acutely toxic, such as anticholinesterase (anti-ChE) insecticides. Use of an indicator species that does not represent maximum exposure and/or effects could lead to inaccurate risk estimates. Our objective was to test the relevance of a priori selection of indicator species for a study on pesticide exposure to birds inhabiting fruit orchards. We used total plasma ChE activity and ChE reactivation to describe the variability in anti-ChE pesticide exposure among avian species in two conventionally managed fruit orchards. Of seven species included in statistical analyses, the less common species, chipping sparrow (Spizella passerina), showed the greatest percentage of exposed individuals and the greatest ChE depression, whereas the two most common species, American robins (Turdus migratorius) and gray catbirds (Dumatella carolinensis), did not show significant exposure. Due to their lower abundance, chipping sparrows would have been an unlikely choice for study. Our results show that selection of indicator species using traditionally accepted criteria such as abundance and ease of collection may not identify species that are at greatest risk. Our efforts also demonstrate the usefulness of conducting multiple-species pilot studies prior to initiating detailed studies on pesticide effects. A study such as ours can help focus research and resources on study species that are most appropriate. © 2013 Springer Science+Business Media New York.


Walter J.F.,National Oceanic and Atmospheric Administration | Hoenig J.M.,Virginia Institute of Marine Science | Christman M.C.,MCC Statistical Consulting LLC
North American Journal of Fisheries Management | Year: 2014

Abstract: Fishery-dependent catch per unit effort (CPUE) comprises critical input for many stock assessments. Construction of CPUE indices usually employs some method of data standardization. However, conventional methods based on linear models do not effectively deal with the fact that samples are collected with a selection bias or with the problem of filling spatial gaps. Geostatistical interpolation methods can ameliorate some of the biases caused by both of these problems while remaining complementary to traditional linear model-based CPUE standardization. In this paper we present geostatistical estimates of sea scallop Placopecten magellanicus CPUE from tows recorded by onboard observers during an opening of Georges Bank Closed Area II in 1999. By selecting tows for which there was little prior effort (on the basis of accumulated effort measured by vessel monitoring systems), we obtained tows that reflected initial abundance as closely as possible. These tows were used to obtain a variogram which was used in geostatistical prediction of sea scallop CPUE. The kriged mean was substantially lower than the arithmetic sample mean, indicating that a geostatistical approach reduced the influence of repeated sampling in locations of extremely high CPUE and increased the weight of isolated observations in areas of low CPUE. The results produced a map that was qualitatively similar to that obtained from a preseason fishery-independent survey. Overall differences between the two approaches were driven by the extension of predictions into areas at the edges of spatial autocorrelation where kriging predictions approached the grand mean of the data set. © 2014, © American Fisheries Society 2014.


Walter J.F.,National Oceanic and Atmospheric Administration | Hoenig J.M.,Virginia Institute of Marine Science | Christman M.C.,MCC Statistical Consulting LLC
North American Journal of Fisheries Management | Year: 2014

Abstract: Geostatistical prediction can address two difficult issues in interpreting fishery-dependent catch per unit effort (CPUE): the lack of a sampling design and the need to fill spatial gaps. In this paper we demonstrate the spatial weighting properties of geostatistics for treating data collected without a sampling design or with a selection bias, two basic traits of fishery-dependent data. We then examine the bias and precision of geostatistical prediction of CPUE based on fishery-dependent data through simulation. We create data sets with known variograms, sample them with a preference for sites with high abundance, and then estimate variograms and CPUE as the geostatistical mean relative abundance. The variograms obtained from the simulated fishery samples correctly estimated the range but underestimated the sill, and the geostatistical mean substantially improved the estimation of CPUE over the arithmetic mean. Though the geostatistical mean still overestimated the true value, the error was primarily due to prediction into unsampled locations, where predictions revert toward the arithmetic mean. The geostatistical variance at a point, which is a function of spatial autocorrelation and the location of adjacent samples, provides a measure of uncertainty. This variance measures the degree to which predictions are derived from nearby data versus distant observations, which translates the spatial extent of extrapolation into probabilistic terms. In conjunction with conventional standardization methods that account for factors affecting catchability, geostatistical prediction provides an additional tool that reduces but does not eliminate biases inherent in fishery-dependent data and supports the need to predict CPUE in unsampled areas.Received July 26, 2013; accepted June 2, 2014 © 2014, © American Fisheries Society 2014.

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