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Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe3+ to Fe2+ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (–OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss.

Background Despite the widespread use of prescribed fire throughout much of the southeastern USA, temporal considerations of fire behavior and its effects often remain unclear. Opportunities to burn within prescriptive meteorological windows vary seasonally and along biogeographical gradients, particularly in mountainous terrain where topography can alter fire behavior. Managers often seek to expand the number of burn days available to accomplish their management objectives, such as hazardous fuel reduction, control of less desired vegetation, and wildlife habitat establishment and maintenance. For this study, we compared prescribed burns conducted in the dormant and early growing seasons in the southern Appalachian Mountains to evaluate how burn outcomes may be affected by environmental factors related to season of burn. The early growing season was defined as the narrow phenological window between bud break and full leaf-out. Proportion of plot area burned, surface fuel consumption, and time-integrated thermocouple heating were quantified and evaluated to determine potential relationships with fuel moisture and topographic and meteorological variables. Results Our results suggested that both time-integrated thermocouple heating and its variability were greater in early growing season burns than in dormant season burns. These differences were noted even though fuel consumption did not vary by season of burn. The variability of litter consumption and woody fuelbed height reduction were greater in dormant season burns than in early growing season burns. Warmer air temperatures and lower fuel moisture, interacting with topography, likely contributed to these seasonal differences and resulted in more burn coverage in early growing season burns than in dormant season burns. Conclusions Dormant season and early growing season burns in southern Appalachian forests consumed similar amounts of fuel where fire spread. Notwithstanding, warmer conditions in early growing season burns are likely to result in fire spread to parts of the landscape left unburnt in dormant season burns. We conclude that early growing season burns may offer a viable option for furthering the pace and scale of prescribed fire to achieve management objectives.

Background Adhesive capsulitis (AC) of the shoulder, also known as frozen shoulder, causes substantial pain and disability. In cases of secondary AC, the inflammation and fibrosis of the synovial joint can be triggered by trauma or surgery to the joint followed by extended immobility. However, for primary AC the inciting trigger is unknown. The burden of the disorder among the elderly is also unknown leading to this age group being left out of therapeutic research studies, potentially receiving delayed diagnoses, and unknown financial costs to the Medicare system. The purpose of this analysis was to describe the epidemiology of AC in individuals over the age of 65, an age group little studied for this disorder. The second purpose was to investigate whether specific medications, co-morbidities, infections, and traumas are risk factors or triggers for primary AC in this population. Methods We used Medicare claims data from 2010–2012 to investigate the prevalence of AC and assess comorbid risk factors and seasonality. Selected medications, distal trauma, and classes of infections as potential inflammatory triggers for primary AC were investigated using a case–control study design with patients with rotator cuff tears as the comparison group. Medications were identified from National Drug codes and translated to World Health Organization ATC codes for analysis. Health conditions were identified using ICD9-CM codes. Results We found a one-year prevalence rate of AC of approximately 0.35% among adults aged 65 years and older which translates to approximately 142,000 older adults in the United States having frozen shoulder syndrome. Diabetes and Parkinson’s disease were significantly associated with the diagnosis of AC in the elderly. Cases were somewhat more common from August through December, although a clear seasonal trend was not observed. Medications, traumas, and infections were similar for cases and controls. Conclusions This investigation identified the burden of AC in the US elderly population and applied case–control methodology to identify triggers for its onset in this population. Efforts to reduce chronic health conditions such as diabetes may reduce seemingly unrelated conditions such as AC. The inciting trigger for this idiopathic condition remains elusive.

Occupancy patterns of herpetofauna in most tidal freshwater swamps are unknown. Tidal freshwater swamps currently face multiple threats, including salinization, which can influence their associated plant and animal communities. The impacts of salinization to herpetofauna communities in tidal freshwater swamps have not been assessed. To improve predictions regarding these herpetofauna, we conducted surveys in tidal freshwater swamps of the Savannah National Wildlife Refuge located in South Carolina, USA, from March to June, 2016 and 2017, using a variety of methods. Goals included inventorying species, determining communities, examining microhabitat associations, and modeling occupancy to predict the impacts of salinity changes. We detected 8 species of amphibians and 12 species of reptiles in our surveys. Community analyses failed to detect patterns related to measured environmental variables. Species richness and diversity declined along the salinity gradient, but the observed patterns did not match our predictions and may instead be related to site-level heterogeneity. Microhabitat associations were detected for two amphibian species via occupancy analyses. Occupancy and regression analyses indicated soil salinity may be a factor affecting nine species’ occurrences. Amphibian detections may be affected by water depth, pH values, and weather conditions. These results expand our understanding of herpetofauna within an understudied, and threatened, wetland type.

Members of the anthozoan green fluorescent protein (GFP) family display a diversity of photo-physical properties that can be associated with normal and damaged coral tissues. Poritid coral species often exhibit localized pink pigmentation in diseased or damaged tissues. Our spectral and histological analyses of pink-pigmented Porites lobata lesions show co-localization of bright red fluorescence with putative amoebocytes concentrating in the epidermis, suggesting an activated innate immune response. Here we report the cloning, expression, and characterization of a novel red fluorescent protein (plobRFP) from the pink-pigmented tissues associated with lesions on Porites lobata. In vitro, the recombinant plobRFP exhibits a distinct red emission signal of 614 nm (excitation maximum: 578 nm), making plobRFP the furthest red-shifted natural fluorescent protein isolated from a scleractinian coral. The recombinant protein has a high molar extinction coefficient (84,000 M-1 cm-1) and quantum yield (0.74), conferring a notable brightness to plobRFP. Sequence analysis suggests the distinct brightness and marked red shift may be inherent features of plobRFP's chromophore conformation. While plobRFP displays a tendency to aggregate, its high pH stability, photostability, and spectral properties make it a candidate for cell imaging applications and a potential template for engineering optimized RFPs. The association of plobRFP with a possible immune response furthers its potential use as a visual diagnostic and molecular biomarker for monitoring coral health.

Progressive decline in irrigation water is forcing farmers to use brackish water which increases soil salinity and exposes the crop plants to salinity. Maize, one of the most important crops, is sensitive to salinity. Salt tolerance is a complex trait controlled by a number of physiological and biochemical processes. Scant information is available on the genetic architecture of salt tolerance in maize. We evaluated 399 inbred lines for six early vigor shoot and root traits upon exposure of 18-day seedlings to salinity (ECiw = 16 dS m-1) stress. Contrasting response of shoot and root growth to salinity indicated a meticulous reprogramming of resource partitioning by the plants to cope with the stress. The genomic analysis identified 57 single nucleotide polymorphisms (SNP) associated with early vigor traits. Candidate genes systematically associated with each SNP include both previously known and novel genes. Important candidates include a late embryogenesis protein, a divalent ion symporter, a proton extrusion protein, an RNA-binding protein, a casein kinase 1, and an AP2/EREBP transcription factor. The late embryogenesis protein is associated with both shoot and root length, indicating a coordinated change in resource allocation upon salt stress. Identification of a casein kinase 1 indicates an important role for Ser/Thr kinases in salt tolerance. Validation of eight candidates based on expression in a salt-tolerant and a salt-sensitive inbred line supported their role in salt tolerance. The candidate genes identified in this investigation provide a foundation for dissecting genetic and molecular regulation of salt tolerance in maize and related grasses.

Mercury (Hg) is a common environmental toxicant to which humans are exposed regularly through occupational and dietary means. Although selenium supplementation has been reported to prevent the toxic effects of Hg in animals, the mechanisms for this prevention are not well understood. The purpose of the current study was to determine the effects of selenium on the disposition and toxicity of Hg. Wistar rats were injected intravenously with a non-nephrotoxic dose (0.5 μmol kg−1) or a nephrotoxic dose (2.5 μmol kg−1) of HgCl2 (containing radioactive Hg) with or without co-administration of sodium selenite (Na2SeO3). Twenty-four hours after exposure, rats were euthanized, and organs were harvested. Co-administration of SeO32− with HgCl2 reduced the renal burden of Hg and the urinary excretion of Hg while increasing the amount of Hg in blood and spleen. We propose that Hg reacts with reduced selenite in the blood to form large Hg–Se complexes that are unable to be filtered at the glomerulus. Consequently, these complexes remain in the blood and are able to accumulate in blood-rich organs. These complexes, which may have fewer toxic effects than other species of Hg, may be eliminated slowly over the course of weeks to months.

Natural selection drives adaptive evolution, but contrasting environmental pressures may lead to trade-offs between phenotypes that confer different performances. Such trade-offs may weaken the strength of selection and/or generate complex fitness surfaces with multiple local optima that correspond to different selection regimes. We evaluated how differences in patterns of phenotypic selection might promote morphological differences between subpopulations of the amphidromous Hawaiian waterfall-climbing goby, Sicyopterus stimpsoni. We conducted laboratory experiments on fish from the islands of Kaua‘i and Hawai‘i (the “Big Island”) to compare patterns of linear and nonlinear selection, and the opportunity for selection, that result from two contrasting pressures, predator evasion and waterfall climbing, which vary in intensity between islands. We found directional and nonlinear selection were strongest when individuals were exposed to their primary selective pressures (predator evasion on Kaua‘i, waterfall climbing on the Big Island). However, the opportunity for selection was greater for the non-primary pressure: climbing on Kaua‘i, predator evasion on the Big Island. Canonical rotation of the nonlinear gamma matrix demonstrated that individuals from Kaua‘i and the Big Island occupy regions near their local fitness peaks for some traits. Therefore, selection for predator evasion on Kaua‘i and climbing on the Big Island may be less effective in promoting morphological changes in this species, because variation of functionally important traits in their respective environments may have been reduced by directional or stabilizing selection. These results demonstrate that despite constraints on the opportunities for selection, population differences in phenotypic traits can arise due to differences in selective regimes. For S. stimpsoni, sufficient variation exists in other locomotor traits, allowing for necessary levels of performance in the contrasting selective regime (i.e., climbing on Kaua‘i and predator evasion on the Big Island) through many-to-one-mapping, which may be essential for the survival of local populations in an evanescent island environment.

We examine cases of predictor omission defined by the relationship between the set of omitted predictor(s) and a set of remaining predictor(s), both of which are included in the full model. We consider a wider range of omitted predictors than previously studied by systematically accounting for both interaction and correlation between the included and the omitted predictors. Our study highlights the impact of predictor omission on the resulting estimated regression coefficients and their squared standard errors. Theoretical and simulated results are presented to illustrate the impact of predictor omission among cases of interaction and correlation. In our simulated results, bias diverged as correlation increased from zero to one. On its own, interaction amplified bias, but the impact of interaction was worse when combined with correlation. Overall, our discussions surround the known problem of predictor omission with a rigorous framework to quantify bias in the included predictor’s estimated regression coefficient and squared standard error.

Spatio-temporal patterns of flowering in forest ecosystems are hard to quantify and monitor. The objectives of this study were to investigate spatio-temporal patterns (e.g. soils, simple slope classes, slope aspect, and flow accumulation) of flowering around Lake Issaqueena, South Carolina (SC, USA) using plant-flowering database collected with GPS-enabled camera (stored in Picasa 3 web albums and project website) on a monthly basis in 2012 and LiDAR-based topography. Pacolet fine sandy loam had the most flowering plants, followed by Madison sandy loam, both dominant soil types around the lake. Most flowering plants were on moderately steep (17%–30%) and gently sloping (4%–8%) slopes. Most flowering plants were on west (247.5°–292.5°), southwest (202.5°–247.5°), and northwest (292.5°–337.5°) aspects. Most flowering plants were associated with minimum and maximum flows within the landscape. Chi-square tests indicated differences in the distributions of the proportions of flowering plants were significant by soil type, slope, aspect, and flow accumulation for each month (February-November), for all months (overall), and across months. The Chi-square test on area-normalized data indicated significant differences for all months and individual differences by each month with some months not statistically significant. Cluster analysis on flowering counts for nine plant families with the most flowering counts indicated no unique separation by cluster, but implied that the majority of these families were flowering on strongly sloping (9%–16%) slopes, on southwest (202.5°–247.5°) aspects, and low flow accumulation (0–200). Presented methodology can serve as a template for future efforts to quantify spatio-temporal patterns of flowering and other phenological events.

The growth of plantlets during hardening is affected by the tissue culture media in which they were grown. A multi-factor approach to optimizing nutrient ions in media for subsequent ex vitro growth has not been studied. A response surface method was designed to test in vitro plant density (50–250 buds/L), \({\text{PO}}_{4}^{3 - }\) (6.25–10.25 mM), Ca2+ (2–10 mM), and KNO3 (18–100 mM) in low \({\text{NH}}_{4}^{ + }\) on medium as it affected subsequent growth in a 21 days acclimatization period with Curcuma longa genotypes (L35-1 and L22-5). The treatment media were compared with the MS medium. Plants grown on treatment media had higher relative fresh biomass (3.3 ± 0.5 fold from high-density with 42 mM KNO3; 3.7 ± 0.5 fold from low-density with 18 mM KNO3) than MS plants (2.6 ± 0.5 fold) regardless of plant density. Leaf area index from the treatments (67.0 ± 16.4 cm2/bud from high-density with 70.4 mM KNO3; 78.4 ± 16.4 cm2/bud from low-density with 50.7 mM KNO3) was higher than MS plants (22.0 ± 8 cm2/bud from high-density and 36.0 ± 8 cm2/bud from low-density). Shoots from treatment plants receiving 64 mM KNO3, elongated to 8.6 ± 0.9 cm from high-density and 10.9 ± 0.9 cm from low-density. Genotype L22-5 elongated to 6.0 ± 0.6 cm regardless of density, and L35-1 elongated to 6.0 ± 0.6 cm from low-density and to 4.0 ± 0.6 cm from high-density. Raising phosphate 5× to 10× the MS concentration in the pre-hardening media did not influence ex vitro responses. Plants grown on modified low ammonium media can grow faster and larger during acclimatization with increased KNO3, especially from high-density culture that would be preferred in commercial applications.

Spatial and temporal databases that integrate urban tree inventories and soil quality information are needed for modern-day sustainable urban forest management. The objective of this study was to demonstrate the usefulness of low-cost and widely-available technology, such as global positioning system (GPS)–enabled cameras to photo-document sites and cloud-based products and services (Google Picasa and Fusion Tables), to aid in developing sustainable street tree management programs. Google Fusion Tables provide a cloud platform to store, share and map urban tree and soil data over time using internet connected computers, tablets or mobile devices. Although indicators of urban soil quality and best methods to assess it are not yet standardized, we demonstrate here promising indicators that are both useful and easy to incorporate into spatial and temporal databases of trees managed in urban environments. By utilizing technology, we demonstrate that site-specific urban soil quality indicators can be used together with readily-available soil rating systems specific to different plant types as a means to better evaluate and manage conditions for optimal street tree growth and health.

Recently, single-sex classes within public coeducational schools have proliferated across the USA; yet, we still know little about whether and how single-sex science classes influence adolescents’ attitude and affect toward science. This exploratory study expands upon our current understanding by investigating the extent in which female and male students’ enrollment in either single-sex or coeducational science classrooms may influence their academic self-concept in science. Utilizing a quasi-experimental research design, findings suggest that being enrolled in single-sex science classrooms influence how students in this study perceive their abilities to perform and learn in science, particularly for females in single-sex science classrooms.

Cell line passage number is an important consideration when designing an experiment. At higher passages, it is generally understood that cell health begins to decline and, when this occurs, the result can be variable data. However, there are no specific guidelines regarding optimal passage range, and this information is dependent on cell type. To explore these variabilities, low passage D1 cells were thawed (passage 3) and passaged serially until a much higher number (passage 34). Samples were taken every five passages and analyzed for alkaline phosphatase and triglyceride; also, the gene expression of both adipogenic and osteogenic markers was tested. The results indicate that the growth rate of these cells did slow down after passage 30. However, expression of the osteogenic characteristics seemed to cycle, with the highest levels seen at passage 4 and 24. The adipocyte expression levels remained the same throughout the study.

Laurel wilt disease (LWD) is a lethal fungal infection of woody plants in the Lauraceae, including redbay (Persea borbonia). We used forest inventory and analysis (FIA) data from 2003 to 2011 to estimate redbay populations and see if any decline could be observed since the introduction of LWD. Throughout its entire range, the population estimate of redbay was about 862.2 ± 89.8 million in 2003, increasing to 951.8 ± 87.1 million in 2011. However, population estimates from 2003 to 2011 displayed a significant negative curvature, suggesting that the population might start to decline. The population in Georgia significantly decreased from 241.1 ± 11.9 million stems in 2003 to 150.3 ± 7.9 million in 2011. Results at the range-wide scale should be taken with caution, since the FIA estimates are based on a 5-year moving average. However, we show that the FIA data can also be used on a smaller scale. Redbay densities decreased significantly in plots surveyed before and after the reported infection by an average of 89.6 live redbay stems/ha. Density in plots without reported LWD were not statistically different between survey years. We developed a logistic regression model to predict the probability of redbay mortality due to LWD. Number of years since LWD infection was the most significant variable, with every increase in 1 year resulting in a 153.7 % increase in odds of death. Diameter was also a significant predictor, with an increase of 1 cm DBH resulting in a 5.0 % increase in odds of death.

To improve micropropagation and acclimatization of turmeric (Curcuma longa L.), we evaluated the effects of media volume, plant density, macronutrient ion concentrations, cationic ratios [NH4 +]/[K+], and sucrose concentration. Multiplication was highest with low bud density. Yield of new plants was highest with high bud density, the most sucrose, the highest concentration of macronutrients, and the greatest volume of medium. However, maximum plant size required low-density, reduced sucrose and elimination of NH4 +. The largest plants grew quickest during greenhouse acclimatization when macronutrients were lowered to 20 mM. In a follow-up experiment, media volume was set at 40 mL with 5% sucrose with NH4 + reduced to 5 mM, and the effects of varying P, Ca, Mg, KNO3, and bud densities were assessed. The largest plants were produced at low density. More importantly, at high density the optimal concentrations of P, Ca, Mg, and KNO3 predicted plant size that was nearly equal to the maximum value from low-density cultures in the prior experiment. Growth of plants during greenhouse acclimatization was increased by modifications of in vitro medium with plants cultured with 3.32 mM P, 4.5 mM Mg, and 37 mM KNO3 predicted to grow most rapidly. The effect of starter fertilizer in the greenhouse mix was much less than the effects of P, Mg, and KNO3 in vitro. These results showed (1) optimal media formulae for different stages of micropropagation and (2) process-related factors such as plant density and media volume affected the optimal nutrient concentrations.

Farmers and extensionists can use forecasts about agro-climatic conditions to reduce risks of agricultural production. Eighteen extension agents, researchers, consultants, and farmers provided feedback about decision support tools that utilize such forecasts during focus groups that were conducted in Florence, South Carolina on January 14, 2011. Climate Risk and County Yield Database were the tools most selected as potentially useful for agricultural extension in South Carolina. An irrigation scheduler was the most frequently mentioned tool to be developed. Also, a survey of Clemson University’s extension personnel was conducted in January and February 2011 to assess interest of South Carolina’s growers and producers in using climate forecasts, eleven potential uses of climate forecasts by extension’s clientele, and potential usefulness to extensionists of twelve specific forecasts. Clemson’s extensionists represent approximately 97 % of the state’s agricultural extensionists. They are more likely than not to agree that growers and producers are interested in using climate forecasts. Most of the state’s extension personnel also think that farmers could use a climate forecast to improve irrigation management and planting schedules. A majority of the state’s extensionists thinks that a freeze alert could be useful to them and the proportion that thinks the forecast could be useful exceeds the proportion that thinks any other forecast could be useful. Most extensionists also think that a forecast of plant moisture stress could be useful to help farmers schedule irrigation. The key survey results are remarkably similar to those from surveys of extension personnel at North Carolina State University in early 2009 and University of Florida in late 2004.

Hummock and hollow microtopography is pervasive in tidal freshwater swamps. Many tree species grow atop hummocks significantly more than in hollows, leading to the hypothesis that hummocks provide preferred locations for maximizing physiological proficiency of inhabiting trees that experience repeated flooding. We used thermal dissipation probes to measure the ecophysiological proficiency of a very flood-tolerant tree, Taxodium distichum, as manifested through in-situ changes in sapflow (a proxy for transpiration) in 11 trees on hummocks and 11 trees in hollows. Overall, sapflow increased significantly by 3.3 g H2O m−2 s−1 (11 %) in trees on both hummocks and hollows during flooding, contrary to our expectations. We found no significant differences in sapflow rates between T. distichum trees positioned on hummocks versus hollows in relation to discrete flood events. Coincidentally, hummock elevations were equivalent to the flood depths that promoted greatest physiological proficiency in T. distichum, suggesting a physiological role for the maintenance of hummock height in tidal swamps. While we reject our original hypotheses that flooding and positioning in hollows will reduce sapflow in T. distichum, this research reveals a potentially important feedback between hummock height, flood depth, and maximum tree physiological response.

Behavior plays an important role in mediating relationships between morphology and performance in animals and, thus, can influence how selection operates. However, to what extent can the use of specific behaviors be associated with particular types of selection on morphological traits? Laboratory selection analyses on waterfall-climbing gobiid fishes were performed to investigate how behavioral variations in locomotion can affect patterns of linear and nonlinear morphological selection. Species from sister genera (Sicyopterus stimpsoni and Sicydium punctatum) that use different climbing behaviors were exposed to similar artificial waterfalls to simulate a controlled selective regime involving the climbing of a nearly vertical slope against flowing water. Juvenile S. stimpsoni “inch up” waterfalls by alternate attachment of oral and pelvic suckers with little axial or fin movement, leading to straightforward expectations that climbing selection should favor morphologies that improve drag reduction and substrate adhesion. In contrast, juvenile S. punctatum climb using substantial axial and fin movements, complicating expectations for selection patterns and potentially promoting correlational selection. Comparisons of directional, quadratic and correlational selection coefficients for various morphological traits and trait interactions indicated that these species showed different selection patterns that generally fit these predictions. Both directional and correlational selection patterns were different between the species, and on average were stronger in S. punctatum compared to S. stimpsoni. Stronger selection in S. punctatum may be related to its climbing style that requires more integrated movement of the fins and body axis than S. stimpsoni, promoting dynamic interactions among body regions within a complicated hydrodynamic environment.

Soybean somatic embryos were developed as a model for investigating the developmental relationships of lipid biosynthesis and accumulation in this important crop. Batch cultures of embryos grown for 8 wk in liquid culture medium exhibited typical sigmoidal growth kinetics as they passed through characteristic globular, heart, torpedo, and cotyledon stages. Exponential growth occurred for the first 4 wk in culture with net growth terminating when total embryo fresh weight per culture flask reached a maximum of 4–4.5 g at 6 wk. This was followed by a slight decrease in embryo fresh weight (FW) and the onset of apparent tissue senescence as judged by yellowing and browning of embryos. On a FW basis, embryos accumulated up to 4% protein, 2.5% soluble sugars, 1.9% starch, and 1.5% lipid relatively early in development. Levels decreased to 0.8% protein, 0.5% soluble sugars, 0.03% starch, and 0.09% lipid at the end of the culture period. On a mass percent basis, lipid extracts were comprised of approximately 80–90% polar lipid early in embryo development. This shifted to 56% storage lipid (triacylglycerol) and 44% polar lipid after 4–5 wk in culture and then reverted back to 91% and 9% polar vs. storage lipid, respectively, by the end of the 8-wk culture period. On the average, polar and storage lipid fractions were comprised of 24% palmitic acid, 7% stearic acid, 8% oleic acid, 36% linoleic acid, and 26% linolenic acid. However, the amounts of linoleic and linolenic acids declined sharply during embryo senescence at the end of the culture period, with corresponding increases in the combined amounts of palmitic and stearic acids. This is the first report that documents the progress of storage reserve accumulation in soybean somatic embryos in relation to their continuous growth in liquid batch cultures.

In the greenhouse and container nursery production industry there is potential for runoff of nitrogen (N) and phosphorus (P), which may contaminate surface and groundwater. Since the 1950s constructed wetlands (CWs), as a simple, low-technology method, have been shown to effectively treat agricultural, industrial, and municipal wastewater. We investigated the N and P attenuating potential of three floating hydrophytes planted in a laboratory-scale subsurface flow (SSF) CW system. Over an 8-week period plants were supplied with N and P (0.39 to 36.81 mg·L−1 N and 0.07 to 6.77 mg·L−1 P) that spanned the rates detected in nursery runoff between the discharge and inflow locations of a commercial nursery currently employing CWs. Whole plant dry weight was positively correlated with N and P supplied. Highest N recovery rates were exhibited by water hyacinth (Eichhornia crassipes [Mart.] Solms.) and water lettuce (Pistia stratiotes L.). P recovery rates were similar for water hyacinth, water lettuce, and dwarf redstemmed parrotfeather (Myriophyllum aquaticum [Vell.] Verdc.). These floating hydrophytes can be cultivated in a SSF CW to remediate runoff losses of N and P. The possibility exists for integrating them into a polycultural remediation system that includes emergent aquatic macrophytes for processing and polishing nursery/greenhouse wastewater.

The aim of this work was to test the putative involvement of members of the ABC superfamily of transporters on folic acid (FA) cellular homeostasis in the human placenta. [(3)H]FA uptake and efflux in BeWo cells were unaffected or hardly affected by multidrug resistance 1 (MDR1) inhibition (with verapamil), multidrug resistance protein (MRP) inhibition (with probenecid) or breast cancer resistance protein (BCRP) inhibition (with fumitremorgin C). However, [(3)H]FA uptake and efflux were inhibited by progesterone (200 microM). An inhibitory effect of progesterone upon [(3)H]FA uptake and efflux was also observed in human cytotrophoblasts. Moreover, verapamil and ss-estradiol also reduced [(3)H]FA efflux in these cells. Inhibition of [(3)H]FA uptake in BeWo cells by progesterone seemed to be very specific since other tested steroids (beta-estradiol, corticosterone, testosterone, aldosterone, estrone and pregnanediol) were devoid of effect. However, efflux was also inhibited by beta-estradiol and corticosterone and stimulated by estrone. Moreover, the effect of progesterone upon the uptake of [(3)H]FA by BeWo cells was concentration-dependent (IC(50 )= 65 [range 9-448] microM) and seems to involve competitive inhibition. Also, progesterone (1-400 microM) did not affect either [(3)H]FA uptake or efflux at an external acidic pH. Finally, inhibition of [(3)H]FA uptake by progesterone was unaffected by either 4-acetamido-4'-isothiocyanato-2,2'-stilbenedisulfonic acid (SITS), a known inhibitor of the reduced folate carrier (RFC), or an anti-RFC antibody. These results suggest that progesterone inhibits RFC. In conclusion, our results show that progesterone, a sterol produced by the placenta, inhibits both FA uptake and efflux in BeWo cells and primary cultured human trophoblasts.

Recycling irrigation water is a common practice at ornamental plant nurseries for conserving water; however, it poses the risk of sourcing and dispersing waterborne plant pathogens, especially species of Phytophthora. Slow sand filtration is a water treatment process that can remove pathogens from water, but the slow rate of water treatment may limit its application at nursery operations. In this study, four novel substrates (crushed brick, calcined clay, polyethylene beads, and Kaldnes® medium) in addition to sand were examined to determine how effective each substrate was at removing zoospores of Phytophthora nicotianae from water. The effects of substrate physical parameters, substrate depths (0, 5, 10, 20, 40, and 60 cm), and microbe density (after nursery effluent was recirculated through each substrate for 21 days) on zoospore removal by each substrate were quantified. Sand was the most effective physical filter and supported development of the best biological filter for removing zoospores. Sand columns 40 and 60 cm deep removed zoospores completely using physical filtration alone, and zoospore removal by sand at 10- and 20-cm depths was increased with the addition of biological filtration. Kaldnes® medium and polyethylene beads were the least effective filtration substrates under all conditions tested. After 21 days of recirculating nursery effluent through substrate columns, microbe density in and zoospore removal by all substrates increased. With further optimization, crushed brick may have potential to be utilized as a recycled material for a slow filtration system focused on removing plant pathogens from irrigation water.

Caveolae are flask-shaped membrane invaginations present in most mammalian cells. They are distinguished by the presence of a striated coat composed of the protein, caveolin. Caveolae have been implicated in numerous cellular processes, including potocytosis in which caveolae are hypothesized to co-localize with folate receptor α and participate in folate uptake. Our laboratory has recently localized folate receptor α to the basolateral surface of the retinal pigment epithelium (RPE). It is present also in many other cells of the retina. In the present study, we asked whether caveolae were present in the RPE, and if so, whether their pattern of distribution was similar to folate receptor α. We also examined the distribution pattern of caveolin-1, which can be a marker of caveolae. Extensive electron microscopical analysis revealed caveolae associated with endothelial cells. However, none were detected in intact or cultured RPE. Laser scanning confocal microscopical analysis of intact RPE localized caveolin-1 to the apical and basal surfaces, a distribution unlike folate receptor α. Western analysis confirmed the presence of caveolin-1 in cultured RPE cells and laser scanning confocal microscopy localized the protein to the basal plasma membrane of the RPE, a distribution like that of folate receptor α. This distribution was confirmed by electron microscopic immunolocalization. The lack of caveolae in the RPE suggests that these structures may not be essential for folate internalization in the RPE.

Saccharum robustum Brandes & Jesw. ex Grassl has been suggested as the immediate progenitor species of cultivated sugarcane (S. officinarum L.) [4]. Chromosome pairing and assortment in these two species were previously studied by genetic analysis of single-dose DNA markers in parents in and 44 F1 progeny of a cross between euploid, meiotically regular 2n=80S. officinarum ‘LA Purple’ andS. robustum ‘Mol 5829’ [2]. This same population was subsequently clonally propagated and evaluated in replicated trials for quantitative traits important to sugarcane breeders. Numbers of stalks, tasseled stalks, and stalks with smut, and the average diameter of two stalks were determined one day prior to harvest. At harvest, plant material from each plot was weighed and evaluated for pol (sucrose content) and fiber percentages. Clones were significantly different (P

The effect of soil waterlogging and nutrient supply on plant nutrient accumulation and distribution was investigated for two genotypes of winter wheat (Triticum aestivum L.) differing in waterlogging resistance, ‘Bayles’ and ‘Savannah’. Plants were grown in waterlogged or drained sand and fertilized with half-strength or full-strength Hoagland's solution. Waterlogging reduced the concentrations of N, P, K, Mg, and Zn in leaves and stems and increased the concentrations of those elements in the root system. The effects were greater for waterlogging-sensitive Bayles than for waterlogging-resistant Savannah. Higher concentrations of Fe and Mn were found in waterlogged plants compared to the control plants for sensitive Bayles. Waterlogging increased the proportion of N and Zn in the root system and decreased that of K in stems for Bayles. The proportion of Fe increased in leaves and stems for Bayles and Savannah under waterlogged conditions, but to a greater extent for Bayles. Doubling the concentrations of all major and minor nutrient elements supplied to the waterlogged rooting medium improved plant nutrient status and enhanced plant dry matter production.

Somatic embryos are being considered as an alternative material for in vitro germplasm conservation of sweet potato [(Ipomoea batatas (L.) Lam.)]. Picolinic acid was tested for somatic embryo production in sweet potato apical meristem tip cultures. Low level (0.2 mgl-1) of picolinic acid combined with kinetin or 6-benzylamino purine (6-BAP) (1.0 and 2.0 mgl-1) suppressed shoot growth and induced callus proliferation. Increased amount of picolinic acid (2 and 3 mgl-1) in combination with kinetin (0.25 and 1.0 mgl-1) induced direct somatic embryogenesis from apical meristem tips of variety Regal but not in Jewel. The primary embryos matured and germinated bipolarly yielding whole plantlets and unipolarly producing embryogenic hyperhydrated-fasciated shoots. The hyperhydrated-fasciated shoots, when cultured in picolinic and kinetin-enriched medium, produced secondary embryos. The secondary embryos also germinated bipolarly and unipolarly, resulting in subsequent cycles of embryogenesis. This recurrent embryogenesis ensures maintenance and proliferation of embryogenic tissues. Somatic embryos were also formed in mannitol-induced hyperhydrated shoots in response to picolinic acid and kinetin or 6-BAP treatment. Embryogenesis did not occur in non-hyperhydrated leaf, petiole, and internode sections.

Cultivar Peking has been extensively used as a source of resistance to Race 3 and Race 5 of soybean cyst nematode, Heterodera glycines I., and Peking genes for resistance are present in a wide range of resistant soybean cultivars. Peking is also used as a host differential in the soybean cyst nematode race classification system. Thirteen Peking lines maintained in the USDA Soybean Germplasm Collection and in several breeding programs were surveyed using RFLP and RAPD markers for genetic characterization. Based on the molecular diversity combined with reaction to soybean cyst nematode, Peking genotypes from a common original source were identified. Peking lines PI 297543 (introduction from Hungary), and PI 438496A, PI 438496B and PI 438496C (introductions from Russia) represented unrelated germplasms. Identified molecular polymorphism can be used to validate the genetic purity of Peking lines used as host differentials for soybean cyst nematode classification system as well as utilization of an individual germplasm line in genetic-breeding programs.

High-density restriction fragment length polymorphism (RFLP) and allozyme linkage maps have been developed in several plant species. These maps make it technically feasible to map quantitative trait loci (QTL) using methods based on flanking marker genetic models. In this paper, we describe flanking marker models for doubled haploid (DH), recombinant inbred (RI), backcross (BC), F1 testcross (F1TC), DH testcross (DHTC), recombinant inbred testcross (RITC), F2, and F3 progeny. These models are functions of the means of quantitative trait locus genotypes and recombination frequencies between marker and quantitative trait loci. In addition to the genetic models, we describe maximum likelihood methods for estimating these parameters using linear, nonlinear, and univariate or multivariate normal distribution mixture models. We defined recombination frequency estimators for backcross and F2 progeny group genetic models using the parameters of linear models. In addition, we found a genetically unbiased estimator of the QTL heterozygote mean using a linear function of marker means. In nonlinear models, recombination frequencies are estimated less efficiently than the means of quantitative trait locus genotypes. Recombination frequency estimation efficiency decreases as the distance between markers decreases, because the number of progeny in recombinant marker classes decreases. Mean estimation efficiency is nearly equal for these methods.

Hyperglycemia is associated with increased morbidity and mortality in critically ill patients and strict glycemic control has become standard care for adults. Recent studies have questioned the optimal targets for such management and reported increased rates of iatrogenic hypoglycemia in both critically ill children and adults. The ability to provide accurate, real-time continuous glucose monitoring would improve the efficacy and safety of this practice in critically ill patients. The aim of our study is to determine if a continuous, interstitial glucose monitor will correlate with blood glucose values in critically ill children.We evaluated 50 critically ill children age 6 weeks to 16 years old with a commercially available continuous glucose monitor (CGM; Medtronic Guardian®). CGM values and standard blood glucose (BG) values were compared. During the study, no changes in patient management were made based on CGM readings alone.Forty-seven patients had analyzable CGM data. A total of 1,555 CGM and routine BG measurements were compared using Clarke error grid and Bland-Altman analysis. For all readings, 97.9% were within clinically acceptable agreement. The mean absolute relative difference between CGM and BG readings was 15.3%. For the 1,555 paired CGM and BG measurements, there is a statistically significant linear relationship between CGM values and BG (P.0001). A high degree of clinical agreement existed in three subpopulation analyses based on age, illness severity, and support measures. This included some of our smallest patients (that is,12 months old), those who required vasopressors, and those who were treated for critical illness hyperglycemia.In one of the largest studies to date, in a highly vulnerable ICU population, CGM values have a clinically acceptable correlation with the BG values now used diagnostically and therapeutically. Our data contest the theoretical concerns posed by some regarding CGM use in the ICU. The existing medical evidence may now support a role for CGM devices in the identification and management of hyperglycemia in diverse ICU settings.

A previously unexploited method of examining neural spike-trains was applied to data obtained from cells in the visual cortex. Distributions of interspike intervals recorded extracellularly from cat visual cortex under four conditions were analyzed. Stimuli were gratings differing in orientation and spatial frequency. The probability density function of first passage time for a random walk with drift process, which is defined by its barrier height and drift coefficient, was used to characterize the generating process of axonal discharge under resting and stimulus conditions. Drift coefficient and barrier height were derived from the sample mean and standard deviation of the measured inter-spike intervals. For cells with simple receptive fields, variations in the drift coefficient were produced by changes in orientation and spatial frequency. Variations in barrier height were produced only by changes in orientation of the stimulus.

The probability of negative analysis of variance estimates of genetic variance components due to sampling error (Ps) was investigated. The objectives were to evaluate the magnitude of Ps, to compare Ps for estimates of σ A (2) and σ D (2) , and to compare Ps for genetic variance component estimates from the nested and factorial mating designs. Ps was defined in terms of ratios of mean squares and the F distribution was used to calculate probabilities of the negative estimates. The results indicated that Ps is often greater than 0.20 for σ D (2) . It is generally lower for σ A (2) than for σ D (2) , and lower for the factorial mating design than the nested mating design.

Confidence interval estimators have not been defined for dominance to additive genetic variance (θ) and average degree of dominance (δ) for the nested, factorial, and backcross mating designs. The objective of this paper was to describe interval estimators for these parameters. Approximate F random variables were defined for expected mean square (EMS) ratios for linear models with one environmental effect. Approximate 1-α parametric interval estimators were defined for θ and δ using these random variables. Random variables defined for linear models with no environmental effects are not approximately distributed as F random variables because common EMS are involved in the numerators and denominators of the EMS ratios. Delete-one jackknife (jackknife) interval estimators were defined for θ and δ for linear models with zero or one environmental effect(s); In transformed analysis of variance point estimates were used in pseudovalue estimators.

The techniques of duodenal perfusion with polyethylene glycol as a nonabsorbable marker, and cholescintiscan using 99Tc HIDA as a gallbladder bile marker, were used to measure the total duodenal output and gallbladder bile concentration of temocillin after administration of an intravenous bolus injection to each of 6 healthy subjects. We carried out 8 studies, 3 with 0.5g temocillin and 5 with 1g temocillin. The plasma half-life of temocillin was 177 (± 25) minutes [mean (± SD)] and 196 (± 29) minutes with the 0.5g and 1g doses, respectively. Urinary excretion accounted for 38% of the total dose given during the study period of 6 hours, and total biliary excretion was recorded as 2.2% of the given dose for both doses. The mean concentration of temocillin in gallbladder bile was 314.7 (± 273.2) mg/L after the 0.5g dose and 474.5 (± 307.3) mg/L after 1g dose. It was concluded that temocillin is highly concentrated in the normal gallbladder in man.

Abdominal scintiscans were performed and three-day fecal indium-111 radioactivity measured, following injection of indium-111-labeled polymorphonuclear leukocytes, in patients with acute gastroenteritis, enteropathogen carriage, exacerbations of chronic inflammatory bowel disease, and patients without gastrointestinal symptoms. The colon was more commonly inflamed than the small intestine in acute gastroenteritis. Fecal indium-111 radioactivity excretion was elevated in gastroenteritis and in chronic inflammatory bowel disease. The magnitude of the intestinal inflammatory response, as measured by fecal indium-111 excretion, is equivalent in acute gastroenteritis caused by a defined enteropathogen and exacerbations of chronic inflammatory bowel disease. All patients with microscopically detected fecal leukocytosis gave positive intestinal scintiscans, whereas negative scans were obtained on patients without fecal leukocytosis. The results of this study suggest that indium-111-labeled polymorphonuclear leukocytes can be used to study pathophysiology of the enteric inflammatory response in acute infectious gastroenteritis.

Rats were trained in a runway under consistent and partial reinforcement conditions. The reinforcement groups differed in the number of runway halts and reversals. In most cases the competing behavior conformed to the predictions of competing response theories of the partial reinforcement effect. Spontaneous recovery from competing responses occurred between days.

An earlier article reported that one 30-sec nonreinforced goal placement resulted in a facilitation of subsequent runway performance. The present experiment indicated that the effect was reliable, but it greatly modified the interpretation offered in the earlier article.

In two experiments, rats were trained on a fixed-ratio partial reinforcement schedule in a runway. Following training, the Ss were given one latent extinction placement in the goal box prior to their regular running trials. In the first experiment, 5 min. intervened between the latent extinction placement and the first running trial, and testing occurred on two days. In the second experiment, Ss were started in the runway immediately following the latent extinction placement, and all test trials were run on the same day. In both experiments, the latent extinction placement decreased running speeds initially, but on subsequent trials performance was enhanced. It was concluded that temporary facilitation may be expected to occur when mild latent extinction is given following training on fixed-ratio schedules.

From arguments elucidated by D. H. Funkenstein and others, it was hypothesized that the aggressive display of the Siamese fighting fish was under hormonal (i.e., norepinephrine) control. Fighteen visually isolated fish were observed for 10 min. each under a plain water control condition and with norepinephrine bitartrate solutions in their individual living tanks. Significant increases in the frequency of fin extensions and gill flaring responses, as well as increased coloration were found for the drug group. Six fish treated with epinephrine bitartrate resembled fish under the control condition except for color change; all six bleached during observation.

Eighty naive, male rats were trained on activity wheels and then randomly placed in one of 16 groups formed on the basis of days of activity deprivation (1, 2, 4, and 8) and activity deprivation cage (ADC) sizes of 25-, 50-, 100-, and 200 sq. in. After removal from the ADC, the rats were tested in the activity wheels. An increase in cage size produced a negatively accelerated activity curve, reaching asymptote at the 100 in. cage size. The effects for days were unclear, probably as a result of the complexity of the interaction. Additional investigation of the phenomena is being undertaken.

Rats were given partial or consistent reinforcement in a runway while satiated. They were then extinguished while deprived. Measures of runway halts and reversals indicated that the reinforcement groups differed in the frequency of competing behavior during both acquisition and extinction. Spontaneous recovery from competing responses was observed. Results were, in most cases, consistent with an earlier study where Ss were trained while deprived.

54 children, M:F=1:1, with recurrent respiratory infections and with normal sweat sodium, were screened for immunodeficiency, including serum immunoglobulins, nitroblue tetrazolium test, neutrophil and monocyte candida phagocytosis and killing, random locomotion and chemotaxis, and Saccharomyces opsonisation. 33 (61%) patients had at least one immune abnormality, including IgA deficiency 4%, opsonisation defect 19%, neutrophil or monocyte killing: serum dependent 30%, cell dependent 15%, and locomotor defect 26%. Some patients had more than one defect. Two patients with laevocardia and situs solitus had ciliary abnormalities, one transiently, and both had asthma but no immunodeficiency. There was no difference in the incidence of asthma in patients with and without immunodeficiency (17 of 33 v 14 of 21). Bacteria were isolated from sputum in 63% (34 of 54), the commonest organism being Haemophilus influenzae found in 52% with immunodeficiency and 38% without, whereas no difference was found for Pseudomonas (19%), Group A Streptococcus (20%) and Strep. pneumoniae (27%). This demonstrates that significant immunological abnormalities are common in patients with recurrent chest infections, with or without asthma, and are much commoner than ciliary defects in cystic fibrosis or Kartagener's syndrome. Isolated opsonisation defects are uncommon and may only be clinically relevant if associated with other serum dependent defects of phagocytosis and/or killing.